Power question: Will a Coolermaster GX 750w be enough for SLI GTX580s? Voltage Question: I've read around and come across a problem with a few voltage issues with GTX580 being too low and it crashing games and windows sometimes. Does anyone know if the voltage issue is with brand specific BIOSs or all 580s? I think I possibly have it with Deus Ex: HR with it crashing but not sure if its the game or not. If it is the voltages is it as simple as getting an OC prog and turning up the voltages abit and thats it? and in SLI would i have to do it to both cards?
The PSU can supply up to 720w on 12V. SLI 580s use 520W of power at stock speed. http://www.guru3d.com/article/geforce-gtx-580-sli-review/14 This leaves around 200W for the rest of your system, assuming the PSU is brand new. Knock approx 5% off the PSUs max power for each year old it is. This PSU isnt enough, even if seems to work ok. SLI 580 will push a720W (12V) PSU very hard and wear it out much faster. Especially if you overclock either the CPU or GPU. When a PSU dies, it is more likely to go bang if it is under heavy load. Components can be damaged. I wouldnt do it. You may need to bump the voltage or the fan speeds up a little in SLI but you also need to provide good air flow in the case. I have to use stock clocks, max fan and slightly higher voltage to play Crysis 2 with a single 580! fyi
While the PSU would probably run SLI 580, it would strain the PSU very badly and there'd be no headroom for comfort and safety. Capacitor aging would become a problem, you'd have low efficiency, lots of heat and noise... Add the fact that it would probably run it - I wouldn't be that surprised if it didn't. I'd recommend a 1kW PSU just to be safe, but a quality 850W would do the job too. With regard to the voltage question, get MSI afterburner and try bumping the voltage up a little bit to see if it makes a difference. If so, you've got your solution
It'l be fine unless you're planning on overclocking your cards and processor to hell..im currently using it with unlocked(and overclocked/overvolted) 6950s in crossfire and my cpu is at 4.6ghz default voltage..the system is 100% stable..that should give you an idea
Minimum recommended PSU wattage for a HD6970 is 550W, according to AMD. Minimum recommended PSU wattage for a GTX 580 is 600W, according to NVIDIA. By inference, the minimum recommendation for 580 SLI is 100W more than for 6970 Crossfire, which is why you're fine with 750W, but the OP should have 850W.
+1 This PSU is 60A on +12V so even if it works, any peak will lead to crashing and freezing. It is a Bronze certified one, so it is decently efficient, but not the best also... and aging of the PSU will be accelerated. If you overclock any of youre component (CPU or GPU) you will have problems that i'm 100% sure... I would also recomment a Gold certified 850w or Bronze 1000w.
I think a 750w will put your system at risk ,when I went 580sli , I moved from a 850tx the a ax1200 as no good 1k units really impressed me. -DO not get a ax1200 they still have a buzzing problem about to send my second one back.
I heard a system with SLI 580's can take up to 800 watts from the wall, so ideally you want a 900 watt PSU just to be safe rather than be tight on the 800 watt mark.
Wow all good info guys! I'm glad i asked then as I am going to OC and possibly get new MB and CPU! And SAAD, I was running 6870 cfx before my 580 and they were stable, the only issue i was getting was what looked like artifacts in Crysis 2. I was getting big 2d black boxes instead of dust and rubble when bullets ricochet off ground and walls.