dslreports logo
 
    All Forums Hot Topics Gallery
spc
uniqs
23

Krisnatharok
PC Builder, Gamer
Premium Member
join:2009-02-11
Earth Orbit

Krisnatharok to Gordo74

Premium Member

to Gordo74

Re: Proposed Mother of All Builds (MOAB)

Thanks for your thoughts Gordo. I probably will wait until I am ready to take the full custom loop WC plunge and just go for a 1kw unit. I might adjust the size after doing my WC research, but right now I don't know how much extra power the pump/rads will take to cover the CPU and two GPUs.

That definitely is on the long-term to-do list, and will help me get some life out of this build. Imagine a stable 5 GHz on the 3770K...

Moos
Tequilablob
Premium Member
join:2008-12-11
Salt Lake City, UT

Moos

Premium Member

I agree that you should be fine with your 750 watt PSU. Looking at the amperage draw of 2 7970's you will only be pulling about 45 amps (depending on your OC). 1 7970 pulling 270 watts equates into 270/12 = 22.5 amps. Adding a second would put you you around 45 amps. I'm Pretty sure that your 12v rail on that PSU is rated a over 60. I think it would be pretty tough to provide the conditions to actually get both 7970's to pull 45 amps. Worse comes to worse you hit your over voltage protection on the PSU and there's your answer. I think you will be more than fine though.

I am interested in seeing your numbers with the kill-a-watt for comparison purposes when you get the dual setup going. My setup with the 2 7950's OC'd to 1100MHZ and an I5-2500K @ 4.4 Ghz was pulling 550-575w max at the wall using a Kill-A-watt. The highest pull during testing was found using 3dmark Vantage. Ive been watching it under various real world conditions and have not seen it higher than this. During the unigine benchmark it barely breaks 500. Gaming is usually in the 400's with games like Crysis 3 @2560x1440 and BF3 at 5760x1080. Max settings on both games.

On another topic, when I added my second 7950 my temps would get up to about 80C on the top GPU. I added more fans and had to play with placing quite a bit. I tried them in about a million configurations changing locations and exhaust/intake. I found the one configuration that works the best is when I mounted a fan to the HDD cage blowing across 2 GPU's. I have the Corsair Carbide 500r, but your Thor looks similar and I think you could mount a fan to the HDD cage too. I'll post some pics if your interested in seeing them. I have not seen the temps on the top GPU get out of the 60C range with this setup.

Your thread is making me want to upgrade motherboard and CPU!

Krisnatharok
PC Builder, Gamer
Premium Member
join:2009-02-11
Earth Orbit

Krisnatharok

Premium Member

said by Moos:

My setup with the 2 7950's OC'd to 1100MHZ and an I5-2500K @ 4.4 Ghz was pulling 550-575w max at the wall using a Kill-A-watt. The highest pull during testing was found using 3dmark Vantage. Ive been watching it under various real world conditions and have not seen it higher than this. During the unigine benchmark it barely breaks 500.

Have you tried the OCCT PSU stress-test? Running Linpack simultaneously with Furmark is probably the most brutal, short of adding an HDD write test with a large file on top of it...