HELP DECIDE PSU - Page 2

Originally Posted by Catscratch 

Hmm 1kwat should be enough. You giving extra voltage to gpus ? Try this. You probably have GPU-z right. On sensor tab, if there's a 12v reading, check it when overclocking. You can run 2xgpu-z to check both gpu 12v readings. When you hover your mouse over the red graphics next to it, it shows what it was at that point. So see if it drops under 12v

Originally Posted by VW_TDI_02 

I would completely disregard what the 12v says. Software has always been one of the most unreliable ways to measure the voltage coming from the power supply. If you want to check stuff then you are going to need an external meter.
No having a higher stock voltage means that you have less headroom to push the voltage and your overclock.
For SLI 480s you can run that off of a 750 watt power supply and be fine. If you don't believe me here is proof:
http://www.guru3d.com/article/geforce-gtx-480-3way-sli-review/25
Your issue probably has to do with either a driver issue or unstable overclocks but since you say it happens when OCing then it's probably that you have an unstable overclock.

Originally Posted by 47 Knucklehead 

You are into the 740w range as far as power draw goes (by the online PSU calculator, plus a little "fudge factor" for OC'ing the 2 video cards.
Yeah, you COULD go with an 850 ... but I wouldn't. I like having "safety factor" built in to PSU wattage. As a PSU ages, it becomes less efficient and I like to have more overhead than most people.
I'd recommend a good 1000 watt PSU and be done.

Originally Posted by VW_TDI_02 

I would love to see proof of anyone drawing over 900 watts with a 480SLI system. The only way I can see that going anywhere near that would be if they have an SR-2 motherboard and two hex core processors. Honestly I don't even think you can feed a 480 enough power through a single 8 pin and a 6 pin power set up. To be frank I just flat out don't believe an SLI 480s system can pull that much. I've seen Quad-SLI pull that much but never anything remotely close to that from only two 480s.
So in conclusion to that your 1000 watt power supply should easily power this system.
Are you asking if it will be more power hungry if you overclock through the multiplier over overclocking through the baseclock? I would say no and even if it does it would be completely minuscule and negligible. The CPU itself is still running at the same frequency regardless of how you get there. A difference (less then 1 watt) could possibly result from the RAM. When you overclock the base clock your RAM changes as well since those are tied together. Depending on how much you overclock and the options you get for the RAM multiplier you may be forced to run the RAM slightly higher but even that difference would be less then 1 W.
[Edit]
I don't mean to be harsh with that first paragraph but in order for a SLI 480 system to pull over 1200 Watts they would each have to pull around 450 watts each which is way more then I've ever seen in reviews.

Originally Posted by VW_TDI_02 

Do you think you can provide us with a link to the exact power supply you have? Honestly it's probably not worth the hassle.

Originally Posted by VW_TDI_02 

If you can return it and not have to pay a bunch of fees I would say you can go either way. I don't think you will be running a risk or anything like that with your current power supply but there are better power supplies out there. From the looks of it that power supply is actually being replaced by the Cooler Master M2 1000 so I'm not even really sure why it's still being sold on Newegg. If you do decide to get a new power supply I would definitely recommend that you only get power supplies from the following list:
http://www.overclock.net/t/183810/faq-recommended-power-supplies
I also looked up a review for that power supply and it seams like an overall solid power supply. The reason it got some points knocked off from the performance section was because it was missing a screw (strange) but overall it was a relatively solid power supply:
http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story5&reid=166
I also looked at the Grunion review that he did and I couldn't actually see how he was measuring the power. I'm almost positive that he was just measuring it from the wall and unfortunately he doesn't list what power supply he is using so this isn't 100% accurate. Judging by the age of the post (2010) he probably has an 80+ Bronze unit so lets say he has 85% efficiency. Back then very few people had gold level power supplies so I think that's a safe assumption. If he is pulling 1148 Watts from the wall then he is actually pulling much less then that from the actual power supply. Assuming he has an 85% efficiency the rig itself is only pulling 975 watts from the power supply. This is also only during Furmark during which cards pull far more then they ever would while gaming.