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PC Building and Upgrading 101

Serephucus

So:

Recently I've noticed a lot of people posting some truly excellent info, and I'm thinking it would be a horrible shame if all of it went to waste, so with that in mind, maybe we should have it all in one place?

My thinking is that we can have (hopefully) a sticky, detailing everything about everything to do with PC building and upgrading. nesf did a great piece on computer audio, deconduo did an excellent bit on PSUs, and partyatmygaff did one on motherboards just yesturday.

I'm thinking that we'll use this thread as a sort of assembly. People can re-post guides here (and new ones), and they can be refined and critiqued by the rest. When we've got everything, we can do a nice contents-post in a new thread, with every post after that being a separate section, to make things as easy-to-find as possible for newcomers.

The little bit I've just finished is on overclocking. Yes, I realise it might be more applicable to overclocking and modding, but there have been quite a few questions here about it too, and if it's going to be a guide about everything computer hardware, I think OCing deserves a place in there too.

Anyway, to start what I sincerely hope will be one of the most informative threads to grace the Internet: (suggestions/corrections/etc. welcome)

Overclocking
__________________________________________________

Introductory note

This is a section perhaps more suited to the enthusiasts, but it's something almost every new computer builder looks into at one point or another: Overclocking. This guide aims to give you the basics in CPU and GPU overclocking. This guide assumes that you're familiar with the components of a computer, their functions, and can find your way around a BIOS. My recommendation is that you read the whole section relevant to whatever component you’re going to overclock, in its entirety first, then start, using the guide as a reference.

Unfortunately, as regards CPU and RAM overclocking, I am only going to focus on socket 1155 systems. I may add 1366 (my own) at a later date, or if another users wants to write up a 775/AM2/AM3 version, they’re more-than-welcome, but the simple fact is it would just take me too long. Also, in particular with AMD systems, I wouldn’t be doing users any justice, as I haven’t used an AMD system in a few years now, and am not very familiar with them as of this point.

What is overclocking?

Overclocking (OCing) is the process by which computer components - be it the CPU, GPU, whatever - are made to run past their out-of-the-box speeds, thus yielding (among other things) an increase in performance. This is done by changing certain BIOS settings. More on this later.

Should I overclock?

This is something that you need to consider carefully before you go fiddling around in the BIOS too much. Is your computer slower at certain tasks than you'd like? Would you like your games to run a little smoother, or be able to enable a couple of extra graphics settings? If yes to any of these, then odds are OCing might be something to think about. If you're a gamer, and play lots of RTS or MMO games, then you'll stand to benefit quite a bit, as RTS and MMO games are among the most CPU-intensive games around. If you're more into FPS titles, you might be more suited to a GPU overclock (though a CPU OC couldn't hurt either). What you have to figure out is where you're being limited. In a gaming context, this will usually be a toss-up between the CPU and the GPU. The easiest way to do this is to leave a monitoring program open while you're gaming. For your CPU, the Windows Task Manager will display CPU usage over a small period of time. If you see your CPU usage rising to above 95% or so, then an overclock could help. A good GPU monitoring program is MSI's Afterburner. It's also the program I recommend for GPU overclocking.

Now you should think about what sort of overclock you want. Many people only overclock their processors enough so that they're sure that their graphics card(s) won't be bottlenecked. This is often the most cost-effective route, as it means you get maximum performance, at minimal cost in terms of an aftermarket CPU cooler, and your ESB bill. If you're going to be overclocking your graphics card as well, then to avoid bottlenecking, you'll want to scale your CPU overclocking with your GPU speeds. If you want see how far you can push your components, then that's fine too! Just make sure you have what you need to do this effectively and with minimal risk (following sections).

What are the risks?

There is really only one risk (that can't be rectified by a simple reset) when overclocking, and that is the scourge of all computer components: Heat. Because components are being made to run faster than they usually would, more heat is going to be generated, and you'll need to have a way to dissipate this excess. As long as you follow a good overclocking guide (hopefully this one), and have adequate cooling, the risk of anything catastrophic happening will be minimal. Having said that:

I take no responsibility for damages, etc. All users undertake overclocking at their own risk, blah blah, you get the point.

Now, on to the good stuff.

CPU Overclocking
________________________________________

What do I need?

The most important things you need are a motherboard and processor that will allow you to overclock. With Intel's newer processors, overclocking is all-but impossible on all but the K and X variant CPUs, and P67 and Z68 motherboards.

Core i3 & i5 2100 series - Locked

These CPUs are a no-go for overclocking. The multiplier cannot be increase beyond the factory setting.

Core i5 & i7 non-K series - Partially unlocked

These CPUs can be overclocked mildly - The multiplier can be adjusted up to X+4 from the factory setting.

Core i5 2500K & i7 2600K - Fully unlocked

These CPUs’ multipliers can be adjusted for a maximum overclock of 5.2GHz.

If you're not sure, or have an older processor, your best bet is to Google "[processor model] overclock" and see what speeds other people are getting. If they're only slightly above the stock speed, then it's almost-certainly not overclockable. You also need to double-check your motherboard chipset, though on anything earlier than a second-generation i3/i5/i7 board, you'll most-likely be fine.

The next thing you need is a power supply that can handle the extra power draw created from the speed increase. If you've had your build specced out on Boards by someone here, then you most-likely have a high quality power supply and are fine. It's only those people who bought the €20 XtremeCoolGamerPro 800W UltraRaid XXX Edition PSUs that need to be concerned. For reference, most PSUs from manufacturers like Seasonic, Corsair, Cooler Master, Enermax, and Antec are of high quality. Check your PSU from comparisons on other forums to be sure.

Last, but certainly not least: cooling. This comes in two forms; your case, and your CPU cooler. As long as your case has at least two decently quick fans (~1000RPM+) you should have enough ventilation to cope with the extra heat. Just be sure that you have at least one fan pulling cool air in, and at least one pushing air out, either at the back, or top, of the case. That brings us to the CPU cooler. There are two main types of coolers available today. Air coolers and water coolers. An example of an affordable air cooler would be the Freezer 7 Pro Rev. 2 from Arctic Cooling. For about €20 (Q1 2012) you can obtain moderate to high overclocks, though with potentially higher-than-normal noise and/or temperature levels. Examples of high-end air coolers would be the NH-U9B SE2 and NH-D14, both from Noctua. This brings us to water coolers. These must not be confused with a watercooling setup. This usually implies a custom-made loop, comprising separate pump, CPU block, radiator and tubing. The water coolers I'll be talking about for this piece are closed-system, single piece cooling solutions, such as the Corsair H70. These typically offer quieter operation and lower temperatures than all but the best air coolers though can be more expensive.

How is it done?

The CPU’s speed is calculated by multiplying the base clock (BCLK) by the CPU multiplier. For example, Intel’s i5 2500K comes by default with a multiplier of 33. Multiply this by the BCLK (100MHz) and you get 3300MHz, or 3.3GHz. The RAM frequency is derived by multiplying the BCLK by the memory multiplier in much the same way.

The basic methodology for overclocking is to increase either the BCLK or CPU multiplier until either the system becomes unstable, or too hot. So the first thing you should try to increase is the CPU multiplier. Raise it by one, keeping all other settings the same, and then boot back into Windows. If you can successfully do this (if you can’t, you have a problem) then we can try and test the overclock for stability.

A note on BCLK overclocking though: While you can increase the BCLK, it’s problematic. Because the base clock controls everything in your system – from the memory frequency to your PCI lanes and I/O – when you increase it, everything runs faster, not just the CPU. This can lead to a lot of instability problems, and to be quite honest, is better left alone. At most, you might be able to increase the BCLK to 106MHz without affecting instability, but in the interests of simplicity (and well-rounded numbers) my advice would be to ignore it as an option entirely.

A second note on power-saving features. While in previous generations of processors power-saving features such as C1E and SpeedStep sometimes adversely affected overclock stability, this does not appear to be the case with 1155 CPUs, therefore, I’d recommend that unless you’re going for very high overclocks (5.0GHz or more) that you leave them enabled to save power.

Testing for stability

Well what everyone has to remember here is that there is a difference between "benchmark" and "stress test". A benchmark is used solely to gauge performance. You run a pre-defined test, and you get a number back. A stress test on the other hand is used for stability. You don't get any sort of rating, you just get a pass, or failure.

So, to start off: I don't bother with CPU benchmarks at all, really. I don't do any video transcoding, or anything like that, so I don't need to know exactly how fast my CPU is. As long as it doesn't bottleneck my games or applications, I don't much care, so I'm only going to talk about CPU stress tests here. One of the best - and an old favourite with many, is Prime95. This has three different tests within it, and you'll be asked to choose one upon running.
Small FFTs is usually the best to give the quickest indicator of stability. Usually, errors will show up here within an hour.
Large FFTs, tends to stress the parts of the CPU that aren't the core - cache, controller, etc. - and to be honest, I don't use it a whole lot.
The last Prime95 test is Blend. This tests everything in your CPU, as well as your memory.

The next CPU test that I use is called Intel Burn Test (IBT). This uses the Linpack algorithm, and is the same test used by Intel to bin CPUs. You want to run it at its maximum settings, for a minimum of 5 passes. If you're going for long(er)-term stability, try 20-25, but I wouldn't use more than that - Linpack isn't really something you want to leave running for 24 hours like Prime. For complete stability in an overclock, I usually use IBT for 5-10 passes each increment, as well as about 15 minutes of Small FFTs. When I've found an overclock I'm happy with, I use 24 hours of Blend, 24 hours of S-FFTs, and about two hours of IBT. If it passes all that - along with the usual games / whatever else I normally do, of course - then I deem a CPU OC stable.

Now: Temperatures. While running these stress tests, you’ll want to keep an eye on your temperatures, making sure they don’t exceed the specified maximum temperature set down by Intel (much). In the case of the 2500K for example, Intel specifies that for long-term usage, the processor should not exceed 72.6°C. What must be made clear here though, is that the temperature specified by Intel is tCase. This means it’s the average temperatures across the CPU heatspreader, not the individual cores (tJunction), which usually run hotter. Because of this, if you see cores running at 75-80°C on your 2500K (or 5-8°C above tCase for your particular processor) during a test, this is ok, though it is at the upper-limit. Expect also to see quite a difference between core temperatures, sometimes as much as ten degrees. This is normal, and is usually down to imperfect contact between the CPU, and the heatsink. This is not to say it’s incorrect; we’re talking about tiny abnormalities here. It should also be noted that IBT will usually exhibit higher peak temperatures than Prime, unless Prime is left running for 12-24 hours. HWMonitor is an excellent program for monitoring (among other things) CPU temperatures.

Tell me how to overclock already!

Fine, fine! To start off, boot into your BIOS. If you’ve tried overclocking before, it would be best to load defaults, and restore any hard drive or boot settings from there, to ensure all overclocking-related settings are as they should be.

Start by increasing your CPU multiplier by one. Save this and boot back into Windows. Run whatever stress tests you’d like, though I’d recommend a minimum of 15 minutes of IBT.

If this is stable, boot back into your BIOS and up the multiplier another notch. If it’s not, and your temperatures are still in the green, increase the CPU voltage (vCore) one notch, and test again. If at any point your temperatures have gone above the numbers outlined earlier, then you’ll need to drop the multiplier down one. Depending on what you’ve changed, you might also be able to drop the voltage down a notch.

The most important thing to remember here is that you must only change one thing at a time! If you start making a bunch of changes and something goes wrong, you’re going to have a hell of a time figuring out what caused the problem. Hopefully, if you follow the above, you’ll be able to achieve your desired overclock. It’s best to start from the beginning with a goal, rather than with a “we’ll take it as we go” attitude.

GPU Overclocking
________________________________________

What do I need?

As with CPU overclocking, you’ll need a compatible graphics card, a case capable of ventilating any excess heat, a power supply capable of supplying the necessary power, and as always, the appropriate cooling.

As far as a case goes, it requires similar traits to that of a good case for CPU overclocking. As long as you have at least one fan pulling, and one fan pushing air, you should be fine, though a side intake fan can also be helpful, particularly with multi-GPU setups. In fact, I’d go so far as to say it’s a requirement if running SLI or Crossfire.

A good PSU is a particular must for GPU overclocking, as high +12V amperage is one of the main characteristics of a good quality power supply. Most modern high power graphics cards such as the HD7970 or GTX 580 (Q1 2012) would require about 40A to leave enough room to have enough comfortable headroom to cope.

As for the GPU cooler, on most cards, a fairly high overclock can be achieved with the stock cooler (though it will be loud as hell). Many companies ship cards with custom coolers, that are often more powerful and quieter than their reference counterparts. Though these keep the cards cooler – and are therefore better for our purposes – they have one big disadvantage: They dump virtually all of that heat back into the case. As you can imagine, having a good case becomes even more helpful here.

How is it done?

For our overclocking, we’ll be using MSI Afterburner. Though released by MSI, this application will work with all cards from AMD and NVIDIA, regardless of brand. With this program, you can monitor almost everything about your card - GPU temperature, memory usage, framerate, core and shader clocks, core voltage, and so on.

Overclocking your graphics card is somewhat simpler than the CPU in certain respects. When you open Afterburner, you’ll see a series of sliders on the left. From top to bottom, these control: Core voltage, core clock, shader clock, memory clock, and fan speed. We will changed some of these to overclock the card.

Testing for stability

While overclocking, you’ll want to manually set your card’s fan speed to something higher than it would otherwise be. You can either set it to 100%, or whatever the highest fan speed you can tolerate (in terms of noise) is. Every time you increase clocks or voltage, you’ll want to run appropriate tests. I don't know about AMD GPUs, but NVIDIA recently changed the type of memory is uses in its GPUs, with the result that the 4xx/5xx series GPUs almost never show artifacts now, so tests like Furmark don't really work as well as you'd think. The best test, is to play the most intensive game you can - jack up the AA if it's not stressful enough - and just keep playing. If you see drops in performance, and your temps are still ok, then it's the card throttling for stability reasons, and you know your OC isn't stable. For testing, benchmark loops or heavy gameplay will almost always be better than synthetic stress tests. Don't ask me why, they just are. As for good benchmarks and/or stress tests to use, 3DMark 11, Heaven 2.5, GTA IV, Just Cause 2, and pretty much any other modern games with a built-in benchmark is a good bet.

A word on temperatures. Generally speaking, graphics cards from both the red and the green time are fine with anything up to around 100°C as an absolute maximum. In-game, I would call 95°C your maximum acceptable-but-highly-uncomfortable temperature. Try to keep things in the 80s if possible.

Overclocking

On newer AMD and NVIDIA cards the core and shaders are directly linked, so changing one proportionally changes the other. So, we’ll start by upping the core clock 10MHz. Simply move the slider to the right, and hit apply down the bottom right. Then it’s time to open up 3DMark, or whatever other tests you're using, and check for artifacts and/or drops in performance that would indicate instability. If all’s well, and your temperatures are ok, keep upping the core clock, testing as you go.

Once you reach a point of instability, and assuming your temperatures are ok and you want to keep going, you’ll need to increase the voltage. This is where problems can arise. It is entirely possible to ruin your card when overvolting, so be sure to monitor your temperatures. In this regard, graphics cards are more fragile than CPUs. Some people will say that anything up to 1.15V is fine for NVIDIA cards, and the voltage can be upped even higher with a custom vBIOS, but I’d stick with 1.15, personally. For 6000 series AMD cards, 1.15V is also the highest possible, and what I would stick with.

Ideally, you want to be about 10-20MHz (at minimum) below the lowest instability point. Riding the very edge of the line the whole time you're gaming isn't a good idea for the card's lifespan, so you're better off giving it a bit of breathing room.

Useful Links

Intel ARK – CPU Specifications: Thermal and voltage limits
HWMonitor – PC component voltage and temperature monitoring
MSI Afterburner - GPU monitoring and overclocking

Prime95 - CPU stability test
Intel Burn Test - CPU stability test
3DMark 11 - PC benchmark / GPU stability test

3 Step Overclocking – Overclocking guides from TechREACTION
Overclocking & Modding - Boards.ie Overclocking forum.

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Comments

Monotype

If someone has some good photography talents, we could could build one without too much difficulty.

That reminds me that Deano12345 had some guides on cabling.

http://www.boards.ie/vbulletin/showthread.php?p=62885594
http://www.overclock.net/t/604645/cable-management-101-by-deano12345

deconduo

Monotype wrote: »

:cool: Excellent post deconduo! Very straightforward and clear.

A few suggestions...
The Samsung 830 is looking like a pretty good drive so and it's often priced close to the Crucial M4 so I think it's a worthy competitor.
I'd also throw in the 560 ti to the graphics card list as you can sometimes get good prices on it if someone can't quite stretch to a 6950. The 6950s are going up all the time too, although next month will see some changes to this list.
For hard drives, what about that hitachi drive? Deskstar D series iirc? I wouldn't normally go for hitachi but they're owned by WD now which have always been reliable for me. Sequential read & writes were very high, but access times weren't so good. Still a good option when paired with SSD. Also maybe throw in the WD or Seagate greens for the 2TB. For storage it'll make little difference and with the way hard drives prices are at the moment, any of them could be cheaper.
RAM - Maybe mention that it's for Intel systems that it makes little difference with. There's big differences for Llano, even if it's not the most popular platform. Apparently it's selling well so someone must be buying them.
It might be a good idea to throw a few different motherboard brands in there too. I see scan have started stocking them but they're not always widely available. I suggest one or two MSIs as quality, pricing and reliability has been fairly good this generation.

Well, I suppose you don't want to give too much choice as it only makes people more confused and it means that the guide requires more updating.

I think we could do with a bit more info on PSUs to add to deconduo's PSU guide. A bit of background info on OEMs and maybe a bit about efficiency curves to show people why they shouldn't overbuy with PSUs?
I could type up a bit if people wanted. I wouldn't know enough to tear a PSU down to the components but I could do an essentials guide for builders which everyone can add.

Good point about the Samsung. The M4 is still slightly cheaper for now, but if the 830 gets a speed boost from a firmware update it would definitely be a good choice.

I wouldn't go for Hitachi drives tbh, their fail rate is twice as high as the Samsung drives. I did mention to grab a good deal if you see one, but right now on HWVS the Spinpoints are by far the best choice.

I didn't mention RAM for llano because you really shouldn't be buying it :P

I might throw in a few more motherboards, I based the guide off HWVS so adding stuff from scan might be a good idea.

Monotype

The 830 has gone up €5 from a day or two ago, it's not worth that difference over the M4 now.

To be honest, I've never bought a Hitachi drive myself, but the max speed of 180MB/s vs the 145MB/s or so that the F3 gets is not to be sniffed at. I think that the hitachi was a single platter drive too. The 7K1000.D was a lot cheaper a while back but prices appear to be more settled now with it €3 dearer at the moment.
The F3 is an ageing drive at this stage, so I'd expect/hope for a replacement this year if the research funds are available.

Serephucus

Right, so I'm back from holidays, meaning I'll hopefully have something up in the next few days. College starts Monday, and at some point - probably late next week - my motherboard is going in for an RMA, so I'll be handcuffed a bit, but I'm going to try for a guide on system optimization and maintenance.

Anyone any other ideas?

@PC build video. Perhaps simply compiling a list of good Youtube links? There are a lot of assembly videos already, but if anyone wants to do one - or a text/picture version, fire ahead!

partyatmygaff

I really should get my section on hardware layout finished. I've had an insane amount of work to get through since I started college back on the 16th though so haven't really had much time.

I intend on covering the Motherboard, CPU, RAM, GPU and may have a small section on HDD/SSDs.

Any other major component i'm missing?

Tea_Bag

could really use an indepth PSU guide. i think thats what everyone struggles with the most (i do anyway)

Solitaire, your time to shine

Monotype

Haven't see Solitaire around much lately.

I'll write up a few paragraphs on PSUs, building on deconduo's post. I'm not a PSU guru and Solitaire would probably know more about it than me but I could get the easy bits out of the way and everyone can add to it. It's definitely an article that would need extra care.

[Deleted User]

Can you provide links to Microsoft xp and vista iso images please?
Want to do a wipe and reinstall of my os but can't find iso images online.
Thanks in advance

Tea_Bag

I don't think windows xp was ever released by MS as an iso download unfortunately.

I also can't find vista outside of MSDN, which you need to be a subscriber for

Monotype

I didn't put in the Vista links to ISOs as they've been taken down. You can still get exe installers and bootfiles from digital river but you have to make your own bootable isos.

There's instructions here.
http://www.heidoc.net/joomla/technology-science/microsoft/57-windows-vista-direct-download-links

As it says on this site, support for Vista will be nearing its support end soon so these links might not stay around for long. Alternatively, you can try to dig up other sources to get the full ISOs but you'd definitely want to match up the hashes.
BTW, with Vista, you can just use an ultimate disc and install any version with the one disc (as long as you have the appropriate key to back it up).

XP images aren't as freely available, but if you have an older disc that you want to update, you can slipstream in the service pack and patches with lots of other tweaks with nlite. Instructions here:
http://www.nliteos.com/guide/

jaykhunter

Any chance of someone writing or linking to how to physically build your own pc? i.e. what parts of a PSU cable attach, what goes where... It would really help me out

Monotype

There's a lot of out of date ones floating around but this one looks good:
http://www.tomshardware.co.uk/forum/274745-13-step-step-guide-building

There's also youtube.
http://www.youtube.com/view_play_list?p=6C802C83EE27B7DD&annotation_id=annotation_882316&feature=iv

Make sure to look at the motherboard manual. That will tell you nearly everything you need to know when installling a particular system.

Monotype

Power Supply Units

What is a PSU?

A PSU is responsible for transforming, rectifying and regulating the power that you get from your wall socket for your PC. All the components through which electricity flows rely upon this component, so you should choose wisely.

Why you should buy a good PSU:

Efficiency – save power and money
Your components will last longer – cleaner power, less ripple and noise
Your components are safer – good PSUs will be built to shutdown safely rather than blowing up
Lives up to its rating – bad PSUs do not perform as their advertised wattage claims
Better cables – Cheap ones don’t come with graphics card connectors
Better warranty and support

Modular PSUs
These are PSUs with detachable cables. It’s a handy feature to reduce clutter in a case but they cost more than non-modular PSUs. The only possible downside is cables coming lose or the negligible power loss in having an additional connection in the circuit. You can get cables with sleeves that match up with the colour schemes in a case and if done right, it can look absolutely fantastic!

Does a 500W PSU consume 500W?
No, a PSU draws what it needs depending on the demands of your computer.

PSU efficiency

PSU Efficiency Ratings
Converting the power from the wall to what your PC needs is not a 1:1 process – you lose out some power, mostly in heat. Often 10-20% of the power will just go to waste in this conversion process. In recent years, there’s been a push to reduce the loss and raise efficiency.
Modern PSUs come with ratings 80+, 80+ bronze, 80+ silver, 80+ gold and 80+ platinum. This ratings guarantee efficiency at certain levels of consumption. These levels are 20%, 50% and 100% of a PSU’s rated capacity.

.| 20%|50%|100%
---|---|---|---
80+| 80%|80%|80%
80+ Bronze|82%|85%|82%
80+ Silver|85%|88%|85%
80+ Gold|87%|90%|87%
80+ Platinum|90%|92%|89%

So a 500W bronze rated PSU with a system using 250W will be running at 50% capacity and must be at least 85% efficient. A PSU is expected to achieve these number or above.

Check out the 80+ website and Wikipedia for more info.

Keep your eyes open for faked ratings too!

Efficiency Curve

Here’s an example of an 800W bronze rated PSU’s efficiency curve. You can see that efficiency does not remain constant across a PSU's load. Power consumption of any system will vary depending on what the system is doing at that time. Ideally, you want to keep your power consumption around the most efficient areas. Even when a system is processing a heavy load, it rarely approaches its maximum potential consumption as it would be unusual to have GPU, CPU and hard drives running at maximum simultaneously. Also keep in mind that most machines will spend a lot of time idle or with low consumption such as browsing the web. A PC with continuous heavy load should be equipped with a powerful PSU and vice versa. Therefore, to achieve greatest efficiency, select a PSU appropriate to your needs.

How much Power am I drawing at X efficiency?
NB: PSUs are rated for what they can supply to the computer, not for what they draw from the socket.
So if your PC requires 250W and your PSU is 85% efficient, you will be drawing 294W at the wall. If you were sure that 250W was the maximum power that you needed for a PSU, a 250W PSU would be sufficient.

So does efficiency matter?
The power consumed varies with the amount of work that a PC is doing, so we’ll just keep it simple with some fixed examples. Prices calculated at current ESB prices.

Cheap PSU. Draws 300W for 4 hours a day for 365 days at 75% efficiency.
300 x 100/83 = 400W consumed. €100.61 per year.
Bronze PSU. Draws 300W for 4 hours a day for 365 days at 83% efficiency; 361W consumed. €77.82 per year.
Silver PSU. Draws 300W for 4 hours a day for 365 days at 86% efficiency; 349W consumed. €75.25 per year.

75% efficiency is not unrealistic for cheap PSUs, as some bad ones can dip to the 60s - you can see there could be definitely considerable savings. For 4 hours a day, there’s not a huge saving to be had between the bronze and the silver. In a server running 12-24 hours, this can quickly add up above the price of PSU upgrade - the marginal cost of €20 for a SuperFlower 450W Golden Green (~€63) over the SF Amazon bronze (€42) would be worthwhile.

I would definitely recommend that you look at getting a bronze rated PSU or at the very minimum 80+ to guarantee some baseline for efficiency.

Quality of Power – Ripple and Noise

Ripple and Noise are variations in power that you do not want. A good PSU will keep the voltage supplied stable and constant – not varying above and below. Drops and surges in power can slowly (or speedily) damage your components as well as cause errors & data corruption.

Rails and Over-rating

Modern ATX PSUs power a motherboard and system primarily with 3.3V, 5V and 12V cables. Black is ground. The colours are Orange 3.3V, Red 5V, Yellow 12V. You can remember them by position of the first letter in the alphabet (O then R, later Y).

Each power line (not each wire) is called a “rail”. You’ll see a table of these rails with their voltages and how much current they can supply in a table on the side of a PSU. Sometimes you’ll see multiple 12V rails but that’s not crucially important in most situations. For high wattage PSUs, the 12V rail is divided up like a fuse box or circuit breaker in your house. If there’s a problem with a plug socket in the bedroom, the switch will trip – similarly Over-Current Protection (OCP) will shut down a rail on a PSU.
You’ll also see 5VSB (5V Standby), in case you’re wondering what that’s about. -5V and -12V are rarely used in modern PCs.
Older systems relied heavily on the 5V rail but the heaviest consumption on a system today will be on the 12V. The heaviest consumers are the CPU and GPU. Most good quality PSUs will have at least 90% of their rated output on the 12V rail.

Why should you care about this? Well here’s an example.

Example 1:

Take a look at the specifications for this 650W Seasonic PSU.

P = V x I
Power (Watts) = Voltage (Volts) x Current (Amps)

3.3 x 25 = 82.5W
5 x 25 = 125W
12 x 54 = 648W

Sometimes there are restrictions on how much the rails can use combined, as PSUs often don’t perform well when drawing heavily from some rails or combinations. Read about crossloading here for more detail. So in this example, you could draw 82W from the 3.3V rail or 125W from the 5V or 125W in both of them together. If you add up the rails separately, you’d get a much higher number. You can very clearly see that on its own, the 12V rail can nearly make up the 650W rating by itself and its likely that Seasonic were even being conservative in rating this as 650W.
Example 2:

Cheapo Alpine PSU from dabs for €17. Supposedly 650W.
3.3V 22A, 5V 34A, 12V 36A, 5VSB 2.0A

Total = 3.3 x 22 + 5 x 34 + 12 x 36 + 5 x 2 = 72.6 + 170 + 432 + 10 = 684.6W
Except that there’s probably restrictions on using combined rails, so you’d be lucky to get close to 650W. A PSU can be rated at its peak power which means that they can reach this rating very briefly but not for long. Sometimes ratings can also be based at certain temperatures which don’t live up to real life environment scenarios – i.e., when a PSU is heating up in a case because it is powering a system!
Take a look at the 12V rail. 432W. Most of your power draw will be on this rail, so this PSU is only equivalent to a 450W PSU.

How much power is actually needed?

So how much power do you actually need for a system? Well for a typical system with 2 RAM modules, a single mechanical HD, a DVD drive and a few case fans you are looking at roughly 40-60W excluding the CPU and GPU.

For the CPU under maximum load:

Phenom II X4 @ 4GHz ~140W
i5-2500k @ 4.5GHz ~ 100W
i5-2500 ~ 60W

For GPUs it varies wildly, so look a review at xbitlabs.com to get an idea.
As a quick reference, this chart is useful (for total system consumption including PSU inefficiency):
http://images.anandtech.com/graphs/graph4239/36072.png

If you intend to overclock the GPU, you should research the marginal power demands and adjust your estimates accordingly. Standard overclocks don't increase power draw dramatically but voltage increases, mods and unlocks can increase consumption rapidly.

Where does that leave us? Well for an i5-2500k OC + 560Ti for example, it leaves you at 60W (System) + 100W (CPU) + 160W (GPU) = 320W. Now, a PSU operates best when its between 65% and 85% of its full load. For example, a good 450W PSU would be operating at ~70% under the largest load that this system could pull.

This is the full system power consumption. Ideally you would want a PSU that would put the PSU at ~75% load, so multiply the figures there by 1.25 to get an idea of what sort of PSU you want.

You should note that most websites stating GPU power consumption will measure their consumption (i) including the rest of a system (ii) from the wall socket, so you will have to discount power inefficiency to get a true rating. Reviews on www.techpowerup.com usually give an accurate measurement of GPU power consumption.

Buying above your needs

Should I just buy the 1000W PSU and then I’ll have a load of room for expansion?
You should plan for expansions and always leave a bit of room for random additions throughout the lifetime but a new sound card and extra RAM is not going to cripple your PSU. Be cautious with overbuying PSUs for two reasons:

High end PSUs are expensive.
Efficiency.
PSU efficiency ratings only cover between 20% and 100%, not below 20%.
Suppose we have a light system that runs idle at 90W and load at about 200W.
A 1000W bronze rated PSU, could drop to 70% efficiency at the lower levels but would keep 82% efficient at 200W. For a draw of 90W with a 450W bronze unit, it would be at 82% efficient and 84%-85% for about 200W.
Idle and load consumption with the 1000W PSU would be 128.5W and 244W respectively while the 450W PSU would consume 112.5W and 238W with the second.
It’s only a few watts and you’d save more by changing to an efficient lightbulb, with about €4 or €5 per year. Okay, you’re not going to get rich but it’s something to consider, especially if your PC is idle a lot.

Another possible advantage to buying high rated PSUs, is that fan noise is usually quieter at low load. Some high end PSUs compensate for efficiency drops at low load with additional circuitry so watch out for this in PSU reviews.

PSU Calculators

For a general guideline, these calculators will help you along, but don’t rely on just a wattage rating:
http://extreme.outervision.com/psucalculator.jsp
http://www.overclock.net/t/1140534/psu-calc-final-release

Who made my PSU? - What are OEMs?

Most of the companies who sell PSUs don’t make them themselves.
Those who make the PSUs are known as OEMs (Original Equipment Manufacturers). Many of these OEMs also sell PSUs themselves, such as Seasonic and Superflower.
A few example of PSUs and their OEMs:

Corsair uses mostly CWT and Seasonic as their OEMs
Antec uses Seasonic, Delta and FSP
Kingwin and NZXT use Superflower as their OEMs

It’s an important factor in choosing a PSU; €10 difference might be buying you the exact same internals. Antec’s HCG and Neo Eco, XFX’s Pro series and some of Corsair’s PSUs have been based on Seasonic’s S12II PSU lines. What’s interesting is that these PSUs are often cheaper than Seasonic's own PSUs!
The level of difference between each PSU is variable; it might be just a fan change or slightly cheaper components can be used to save cost. It’s wise to have a look at a company's support, especially warranty length.
It’s also noteworthy that an update by Seasonic in their platform, such as an increase in efficiency may be passed onto the derived products without specifications being updated – for example, recent reviews of Antec’s Neo Eco demonstrate 80+ bronze level efficiency as opposed to the rated 80+.
It’s also helpful to be aware of seemingly reliable brands who switch to unreliable OEMs. Companies also often interchange OEMs for each model along a PSU series. For example, Corsair have switched between CWT and Seasonic for various generations of the TX series.

Which PSU should I buy?

The key to buying a good PSU is reviews. The more reviews, the better. Don't rush to accept any single review as samples can vary, reviewers can be bribed and one group can pick up something that was missed.
The best place to check out first is the PSU Review Database. This is an excellent site which lists the big review sites such as hardwaresecrets, HardOCP, jonnyguru and kitguru. You’ll also see OEM lists and ratings.

PSU brands which are good (general idea, not to be taken as an absolute ruling)

Superflower amazon/golden green/golden king –available on hardwareversand.de
Enermax
Coolermaster modular PSUs
Antec (most of them) – check out before buying the cheap models
Silverstone (most of their modern ones)
Seasonic
XFX
Corsair aside from CX series*
OCZ ZS, ZX, ZT series

*CX v2 or above may be okay but the series tend to be overpriced and a little overated in the power capability suggested by the names. The 430W version can be a good buy as there are a lot of bad PSUs in that price range. If you have the opportunity, the Superflower amazon 450W is a better choice.

PSU brands to avoid (again just a general statement, rule isn’t absolute)

Any cheap PSU lighter than a sponge cake
Any PSU that doesn't have clear, transparent specifications
PSUs that comes with a cases (some Antec/Silverstone or equivalent are OK)
Cooler master cheap models (essentially, just avoid any of their non-modular ones)
Dabsvalue/Best Value
Superflower cheap models
Kiss
CIT

Remember: A manufacturer with a good PSU does not mean all PSUs from that manufacturer are good. Similarly a few bad PSUs from one group doesn’t imply a completely bad set, especially since they can switch OEMs.

Power Supply Connectors.

Here’s a good site showing the connectors on PSUs.
http://www.playtool.com/pages/psuconnectors/connectors.html

The ones you’ll need on a modern PSU are:

24 pin (sometimes as 20+4 as older systems just need 20)
8 pin EPS 12V (sometimes as 4+4, some boards only need 4)
SATA power connectors for your hard drives, optical drives and SSDs
PCI-express cables. These can be 6 pin or 8 pin. Low end cards don’t need additional power. Mid cards will need one (Radeon 6850), higher cards will need a 6 pin and a second 6 pin or 8 pin. The 8 pin connectors are usually detachable to 6+2 for compatibility.
4 pin molex for older hard drives, optical drives and fans.

Additional Information

Can I take my PSU abroad?
It depends on the PSU. Older PSUs will have a switch at the back to change between 230V and 115V. Ensure that this is set correctly if you don’t want to destroy your system. Most new PSUs will automatically switch between various voltage inputs but check the manufacturer’s specifications to be sure.

Graphics card box says I need X number of Watts.
They often overstate the ratings because of the bad PSUs around. Firstly, find out if your PSU is of good quality. Then research actual power requirements for a graphics card.

Can I upgrade my Dell's PSU?
Some Dells will accept any standard PSU. Some do not and you need to be careful.
The first issue is size. Many PC makers will have their own shapes of PSUs with screw holes in differing places and you'll discover that standard PSUs won't fit into the cages holding the old one. The cables are often of unusual lengths to suit the needs of that case design.
Secondly, and very importantly, Dell and possibly other manufacturers have produced proprietary PSUs that don't conform to power pins of the ATX standard! This means that you can destroy a PC by connecting a new PSU! Dell have stopped this in recent years appear to be now using ATX PSUs more regularly. You should still search online for others with experience upgrading PSUs for a particular model to ensure that it follows the standards.

What can happen with bad PSUs?
Jonnyguru - The Bargain Basement Power Supply Roundup
Jonnyguru - Death of a Gutless Wonder
Tom's Hardware - Don't Be Surprised When Your Cheap PSU Blows Up

Links
80+ Ratings
Power factor & Correction
PSU Review Database
Huge PSU list with OEMs and 12V ratings
Tom’s Hardware OEM List
Tom’s Hardware - How Much Power Does Your Graphics Card Need?
Jonnyguru.com – Excellent site for PSU reviews
Jonny Guru’s PSU FAQ
Jonny Guru OEM list

____________________________

Credit of course to deconduo for his parts. Feedback welcome.

____________________________

Serephucus

Excellent post. I had a decent skim through it (will give it a proper read after food), but the only thing I'd say it to mention in that bit towards the end that graphics card power requirements are for the whole computer, not just the GPU. I.e. GTX 580 req. of 600W is for the whole machine (on average), not just the card itself.

Monotype

The anandtech link? OK, added an additional note just before it.

I had mentioned just at the end of the section that GPU power requirements are often quoted with a system and measured at the wall. TBH, that's a complete pain in the arse when trying to figure out graphics consumption but I suppose equipment to measure that would be expensive. I'm not fond of calculating PSUs mainly for this reason. Does anyone know any good lists for accurate consumption?
Hmm... I suppose I should also mention overclocking. How much extra power do people think should be left for a card overclock?

If anyone wants to add more examples or thinks I should add more PSU brands, let me know. I just added the ones that are mostly available here.

Serephucus

RE: GPU overclocks, I'd say around 50-75W, depending on the card.

deconduo

Serephucus wrote: »

RE: GPU overclocks, I'd say around 50-75W, depending on the card.

Depends on what you're doing. If you don't increase the voltage then there's going to be only a small increase in power consumption. Even overclocking the 7970 by a massive 20% (925MHz -> 1125MHz) gave only a 27W increase from the socket:

http://images.anandtech.com/graphs/graph5458/43787.png

When you do start bumping up the vcore you will see the power increasing accordingly, but still nothing significant:

http://www.xbitlabs.com/images/graphics/palit-gf-gtx560-sonic-platinum/zdiagr-pw_xbt.png

Monotype

I suppose I'll leave it a bit open-ended so and just mention your advice. Most people probably wouldn't be doing pencil mods with their first build, so people should be able to fit an average overclock in if they choose their PSU well.

Serephucus

@deconduo, point. I suppose I was going from my own experience - very high overclocks on a power-hungry card. :P

Monotype

Found another link with PSU OEMs. It's a bit out of date, but worth adding to the article, but my powers to edit have expired now.

http://www.jonnyguru.com/modules.php?name=NDArticles&op=Story&ndar_id=24

papajimsmooth

Could someone do a piece on monitors for normal use vs gaming?

Serephucus

That's not a bad idea at all actually, I'll start that one today I think.

jaykhunter

Oh actually, could u include - is there a difference between VGA-to-VGA, DVI-to-DVI and HDMI-to-HDMI cable connecting to the monitor? Like if you have the option of all 3, does it make a difference if you were gaming/watching videos?

thanks buddy

Monotype

If you use
VGA -> VGA, there could be a very slight drop in quality with an LCD as your graphics card is converting from digital to analogue and your monitor is is converting it back again to digital.

DVI and HDMI should be exactly the same as they're both digital signals.

HDMI can carry sound though and not every device that uses DVI is HDCP compatible (i.e., compliant with digital video DRM), so you could run into trouble with blu ray discs and drives.
There's also a few versions of DVI, like ones that output analogue signal and dual-link DVI which is for higher bandwidth.

Too long; didn't read:
DVI and HDMI is the same for your average desktop environment; use over VGA if you can.

ShadowHearth

Very good idea about some sort of piece about monitors.

I know that avg connection should be avoided as plague, but there is more then that.

Response times
Contrast rations
Led, TFT, TN panels
Resolutions etc.

How much is too much for desktop pc etc. I have seen se idiots on YouTube with 3x42inch telly eyefinity setups which look extremely uncomfortable and more annoying then cool or good for gaming etc.

I have some knowledge about monitors, but it is not as much as I would like.

Serephucus

It'll probably be tomorrow before I can get this up - scanning a 260 page book at the moment. >.<

ShadowHearth

Serephucus wrote: »

It'll probably be tomorrow before I can get this up - scanning a 260 page book at the moment. >.<

Ouch lol. Haven't used scanner in 10 years!!! Last time I used it: scanning some porn magazines...

( yeah yeah, Internet was not that awesome back then!

)

Monotype

Addition to Windows guide (Thanks Fluffy):

When downloading large files like the Windows 7 .iso file, you should use a download manager to make life simpler. Being able to continue the download is very important with such large files in case of a dropped connection.
Opera browser features a built in download resume or another separate option is JDownloader.

Serephucus

Woops! I was supposed to do a monitor guide! Completely forgot about this amidst other stuff. At the moment I'm quite busy, so if someone else wants to take this feel free.

Monotype

Hmm... well what kind of depth were you thinking of?

I could type up a bit about the basics like connectors, eyefinity, and your average features/monitor types but I couldn't really explain what the differences between the various IPS panels or touch screens are without a fair chunk of research.

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