PSU selection WATT, advice needed.

Mindas

Hi,
I cannot decide which PSU should I buy 650 watt or do I need 750?

I need quite PC, hi efficiency.



System specs.

CPU: Intel Core 2 Quad Q6600 G0 2400 MHz Kentsfield
RAM: 2 Sticks DDR2 SDRAM
Video Card: NVIDIA GeForce 8400 GS (Passive cooling)
IDE HDD 7200 rpm: 4 HDDs
DVD-RW/DVD+RW Drive: 1 Drive
PCI Network Interface Card: Yes (wifi)
Sound Blaster audigy
PCI SATA RAID Card: Yes (RAID 1)
USB: 1 Device
Fans
Regular: 2 Fans 120mm;
Case ANTEC P180

according to http://extreme.outervision.com/PSUEngine calculator I would need

Minimum PSU Wattage: 358 Watts
Recommended Wattage: 408 Watts



To get best efficiency need to load about 40% -60% of max PSU.

It would be around 700-800W. Am I right?

Any suggestions welcome.

Solitaire

Oh dear...

Your CPU is using ~100W with all four cores running flat-out, if you're running it at stock settings.
Your graphics "card" is a joke (which is totally fine if you're not gaming) and even if it was running a 3D application it would have trouble reaching 20W. It could peak around 25W on a blue moon while running 3D, but as I doubt this system does so very often at all the averge figure would be based on the sub-10W 2D mode.
The rest of your system is drawing ~40W on average, although it could peak up to 120W if all four HDDs were ordered to spin up simultaneously (which usually only happens when loading the OS or waking from hibernation). The former figure is plotted against the 50% load line, the latter against the 100% mark (although it gets trickier if you get a multi-rail PSU).

So your average 12V power requirement would be 12-13A, and you need a PSU with a 12V rail(s) capable of handling 24-26A (theoretical peak is covered by this as its only ~21A). A really decent modern 300W PSU could handle it, as could many decent 330-350W models; the key is the strength of the 12V rails In your case there is one caveat; you have a ton of HDDs with a big maximum theoretical demand (the simultaneous spin-up issue with motherboard-based and cheaper discrete RAID controllers) so I strongly recommend you buy a unirail PSU or a PSU with the main 12V rail greater than the aforementioned 21A, or a dual-rail PSU with the CPU and SATA/Molex (i.e. HDDs) connectors on two different rails.

Of course, if you were going to OC that CPU or intend on converting it to gaming via a major graphics upgrade you'll need something a fair whack stronger, but even then I doubt you'd need more than a decent 550W unit

Mindas

Hi Solitaire,
Thanks for reply
Yes, I am not gaming. Picture editing and data copying from 1 hdd to RAID1 (2 hdd), thats all. Some times its connected 5 hdd at a time.

I had a PSU CoolerMaster 650W EXTREME POWER PSU, which was terrible loudly. One of the hdd had problems with spin up with this PSU.

Then replaced temporary to some 350W noname. Temporary is about one year Until other HDD (Raid1) got bad sectors and so on.

So yesterday have bought Seasonic X-series 650W.
Hope it will be fine for next 5 years and very low noise also.

And power double what I need or more?

Solitaire wrote: »

Oh dear...

Your CPU is using ~100W with all four cores running flat-out, if you're running it at stock settings.
Your graphics "card" is a joke (which is totally fine if you're not gaming) and even if it was running a 3D application it would have trouble reaching 20W. It could peak around 25W on a blue moon while running 3D, but as I doubt this system does so very often at all the averge figure would be based on the sub-10W 2D mode.
The rest of your system is drawing ~40W on average, although it could peak up to 120W if all four HDDs were ordered to spin up simultaneously (which usually only happens when loading the OS or waking from hibernation). The former figure is plotted against the 50% load line, the latter against the 100% mark (although it gets trickier if you get a multi-rail PSU).

So your average 12V power requirement would be 12-13A, and you need a PSU with a 12V rail(s) capable of handling 24-26A (theoretical peak is covered by this as its only ~21A). A really decent modern 300W PSU could handle it, as could many decent 330-350W models; the key is the strength of the 12V rails In your case there is one caveat; you have a ton of HDDs with a big maximum theoretical demand (the simultaneous spin-up issue with motherboard-based and cheaper discrete RAID controllers) so I strongly recommend you buy a unirail PSU or a PSU with the main 12V rail greater than the aforementioned 21A, or a dual-rail PSU with the CPU and SATA/Molex (i.e. HDDs) connectors on two different rails.

Of course, if you were going to OC that CPU or intend on converting it to gaming via a major graphics upgrade you'll need something a fair whack stronger, but even then I doubt you'd need more than a decent 550W unit

Deano12345

That Seasonic is overkill, but its an amazing unit. You'll have no problem with it

Mindas

What means overkill? Is it bad?

Deano12345 wrote: »

That Seasonic is overkill, but its an amazing unit. You'll have no problem with it

Solitaire

It means you didn't need one anywhere near that powerful Nothing's wrong with it though, other than what it probably cost you to buy!