More Power Efficient Build?

IrishMetalhead

Got a pretty nasty electricity bill this week so now I'm looking to cut down on whatever to reduce it next time round and one of things that came to mind is swapping my current build (1 year old) for a more efficient one with a itx mobo, less power hungry i5 or i3 with no overclocking and a 7850 instead of my 6950, I recon I could get €550 maybe €600 (at a stretch) for my current build so that's what I have to go on and this is what I had in mind:

Item|Price
Intel Core i5-3470 Box, LGA1155|€168.91
ASRock B75M-ITX, Sockel 1155, ITX|€72.42
8GB Patriot Viper3 BLACK MAMBA, 1600MHZ, CL 9-9-9-24|€39.80
Samsung SH-224BB bare schwarz|€17.14
XFX Radeon HD 7850 860M Core Edition, 2GB GDDR5|€169.87
Cooler Master Elite 120 Advanced, Mini-ITX, ohne Netzteil|€39.05
Thermaltake Smart Power 530W|€42.69
Asus USB-N13 Wlan USB Stick|€9.90
LogiLink USB 3.0 zu SATA Adapter & Docking System|€17.08
Shipping|€18.99
Total|€595.85

I'll be switching from this:
CPU: AMD Phenom II X4 960T
CPU Cooler: Thermaltake Frio
RAM: 8GB Corsair Vengeance 1600MHz CL9
Motherboard: ASRock 970 Extreme4
Sound Card: Asus Xonar DGX
Graphics Card: Sapphire HD 6950 1GB Daul Fan
WLAN Card: D-Link DWA-552 Xtream
PSU: XFX 650W Core Edt.
Case: CoolerMaster 690 II Advanced, USB 3.0 Windowed Edt.
DVD Drive: Samsung DL DVD-RW (optical drives are all the same so you know yourself)
Plus a multi card reader (generic)
Also have 2 500GB HDD's to put into raid0 and a spare Windows key to throw in to sell it on because I want to keep my SSD and 2 1TB HDD's for the next one.

So over all how much power would I expect so save by switching?

marco_polo

Not a huge amount really if you do the math, certainly not worth an expensive upgrade.

First point is you are actually downgrading from an 80 plus bronze PSU to a less efficient 80 plus one.

Taking the main components, on the GPU you'd save about 50W at full load, 5W idle of power.

For the CPU, I can't really find any detailed reviews for the 960T, but this review compares and i5-3470 to an Phenom X6, measuring total system power. (The 960T seems to be a former hexa core with two cores disabled). As the four core 960T would use a fair amount less power than the 1100T in the the review I'd say a reasonable guesstimate would be in the region of 15-20W idle/50-60W load difference (I'd say it might even be less again but I'll roll with these number).

Lets say the PC was running 24/7 for a year (idle and the with the two main power consuming components fully loaded), so using 25W idle/110W load from above as the approximate total system difference),and taking 17 cent as a rough KWh price.

Running Fully CPU/GPU load for a year: 0.110kW * 24h * 0.17c * 365d = 163.15 euro difference
Running fully idle for a year: 0.025kW * 24 * 0.17c* 365d = 37.20 euro difference.

Obviously neither of these figures are remotely typical of actual usage, but as a typical home PC is probably completely off for most of the day, with a couple of hours somewhat intensive usage in the evening.

I'd say that over the course of a year, the average savings would be much closer to the idle total than the load one to be honest, they are not insignificant if building from scratch but not worth changing everything for either IMO.

Shopping around and switching providers would probably be just as effective.

IrishMetalhead

aye i get ya, didn't noticed the psu i chose was a non bronze so i replaced it with a 450w superflower amazon (altho the led's will annoy me) even tho it's only minimal power difference would i benefit more by switching to a i5 by downgrading the gpu by the smallest margin, as far as i know the 6950 and 7850 are almost identical in performance with the 6950 the smallest bit faster

IrishMetalhead

another thing, a mate of mine gave me his windows 8 key he got from college because he's too keen on sticking to windows 7 like myself so would it be better to install windows 7 or 8 to sell said desktop if i decide to go for it?

marco_polo

IrishMetalhead wrote: »

aye i get ya, didn't noticed the psu i chose was a non bronze so i replaced it with a 450w superflower amazon (altho the led's will annoy me) even tho it's only minimal power difference would i benefit more by switching to a i5 by downgrading the gpu by the smallest margin, as far as i know the 6950 and 7850 are almost identical in performance with the 6950 the smallest bit faster

No point changing the PSU at all though, because the system will only draw whatever it needs. And since the XFX Core also has bronze 80 status it should perform almost exactly the same as the SF450.

If you play alot of games there is probably much greater benefit in switching the GPU as that is the component that spend far more of its time at 100% load and as you say is a relatively small downgrade.

IrishMetalhead

i know that but the problem is trying to sell a desktop without a psu so thats the only reason for getting a new one.
Well i do alot of video editing and rendering aswell so that why i think i might benefit by switching to from a 6950 to a 7850 so i can get an i5 instead would benefit me more since i'll still be able to play all my games at 1920x1080 with a 7850 albeit i'll be loosing 2 hdd's and a os in the process but i guess i'm just looking for an excuse to have a change

marco_polo

IrishMetalhead wrote: »

i know that but the problem is trying to sell a desktop without a psu so thats the only reason for getting a new one.
Well i do alot of video editing and rendering aswell so that why i think i might benefit by switching to from a 6950 to a 7850 so i can get an i5 instead would benefit me more since i'll still be able to play all my games at 1920x1080 with a 7850 albeit i'll be loosing 2 hdd's and a os in the process but i guess i'm just looking for an excuse to have a change

Well if you have a few other reasons on top of the electric bills then by all means fire ahead :pac:

IrishMetalhead

lol only if it were so easy, have herself to convince first XD
so shall i sell it with windows 7 home premium or windows 8 pro?

marco_polo

If you have no preference maybe give the buyer a choice? I don't think it would affect the price too much either way.

ancuncha

i don't know much about this but i imagine for power saving the 1st place to look is the psu
there rated for efficiency by this 80plus rating, somewhat explained here http://en.wikipedia.org/wiki/80_Plus
if your serious about power saving look at a gold level one, i dare say the extra cash now would over the course of the life of the computer be saved back
maby ? http://lb.hardwareversand.de/400+-+500+Watts/41092/Super-Flower+SF450P14XE+Golden+Green+Pro+80plus+gold.article

IrishMetalhead

i'm just going to stick to bronze, gold would be perfect but it's a we bit out of my budget i'm afraid.
had to go with Windows 8 on the spare hdd's turns out Windows 7 has a hard time installing with the AMD Raid controller if you don't have a floppy to install the raid drivers so it was just easier to install 8.
still on the fence about this decision but i jut dunno if all the downgrades is worth it to upgrade to a i5, but then again the idea of an itx system is pretty cool.