OK I'm making this thread in the hopes to help people from having to post a thread asking about how much power they need to run their PC. It seems we get one of these threads every few hours here. So I'm making this quick little reference for users of the 500 series cards. This will give you a ballpark idea of what you will need with your planned setup and if you need to upgrade your PSU or not. Please understand that this is not the "be all end all" of PSU requirements, but a guide to point you in the right direction. I will be referencing a review site that is using an overclocked X58 platform with a power hungry i7 965X C0 CPU. If you're running a Sandybridge setup you can count on your power consumption being a bit less even if you have it overclocked.
 
So without further delay, lets get to it. I'm only including numbers from a single site so that the numbers can be comparable as they used the same setup in each of the tests. (note the peak wattage is for the entire system)
 
2x GTX590 SLI = 890w
http://www.guru3d.com/art...e-gtx-590-sli-review/3
 
Single GTX590 = 503w
http://www.guru3d.com/art...force-gtx-590-review/7
 
3x GTX580 SLI = 933w
http://www.guru3d.com/art...80-3-way-sli-review/14
 
2x GTX580 SLI = 719w
http://www.guru3d.com/art...-gtx-580-sli-review/14
 
Single GTX580 = 447w
http://www.guru3d.com/art...force-gtx-580-review/7
 
2x SLI GTX570 = 578w
http://www.guru3d.com/art...-gtx-570-sli-review/13
 
Single GTX570 = 369w
http://www.guru3d.com/art...force-gtx-570-review/8
 
2x GTX560 Ti SLI = 449w
http://www.guru3d.com/art...x-560-ti-sli-review/14
 
Single GTX560 Ti = 319w
http://www.guru3d.com/art...ce-gtx-560-ti-review/7
 
2x GTX560 SLI = 449w
http://www.guru3d.com/art...-gtx-560-sli-review/14
 
Single GTX560 = 289w
http://www.guru3d.com/art...force-gtx-560-review/8
 
Now here's were we get a little creative since the site didn't review 4 way SLI GTX580s and 3 way SLI GTX570's we have to estimate their power usage by looking at similar setups. I think all of you will agree that the GTX480 and GTX470 consume roughly the same power (if not a bit more) as a GTX580 and GTX570. So here we go:
 
4x GTX580 SLI = 1188w (est)
http://www.guru3d.com/art...-gtx-4way-sli-review/8
note that they even include numbers as they overclock the system further
 
3x GTX570 = 794w (est)
http://www.guru3d.com/art...-2-3-way-sli-review/23
 
Now I realize that the last 2 are subjective but they should give you a rough guideline as to what it's going to take. You'll also notice that I didn't include the GTX550 Ti and lower. That's because well, they are really not power hungry cards from that point as you go down the GPU table. You can safely expect what powers a SLI GTX560 system to power any SLI GTX550 Ti system and lower.
 
Also concerning the numbers above, it is generally a good idea to give yourself about 100w or so of head room with your PSU. So for instance if the setup you're looking at requires 719w like for instance the SLI GTX580 system. You'll want to have at least a 800 - 850w PSU.
 
One final note guys, please remember that the quality of your PSU matters greatly. Don't go buy some cheap Apevia 1000w PSU and think you're good to go. The reality is that those cheap PSUs aren't what they are cracked up to be. Often times they are severely overrated 700w units or even less. The way companies rate PSUs is a bit deceptive. Often times they will rate them for their maximum load and not their continuous load. A PSU that is rated for 1000w max is not able to sustain that load for any real length of time and will most likely fail if asked to do so. Maximum load ratings are only for load spikes or short term. A PSU that is rated for a continuous output is capable of delivering that wattage for any length of time for the operational lifetime of the PSU.
 
Just remember that cheap = cheap, never cut corners on your PSU. This doesn't mean go buy the biggest and highest current PSU you can get. This means simply to buy from trusted and reputable brands like Antec, Seasonic, Sliverstone, Enermax, Ultra, Corsair, PC Power & Cooling and a few others.
 
Hope this helps some of you and if you have any questions just ask

Great job bro!

/agree should be up there as a sticky for reference.

Glad you guys like it. Also if anyone is interested, I can put together one for the 400 series, but not sure if there is a need for it anymore.

I appreciate all the time you put into this,it was helpful ty.

very nice, i wonder what x3  480's would pull with a 4ghz oc on a 920...lol

i know PSU calculators are estimated and often overkilled, but i can't help but paranoid and just buy extra headway JUST IN CASE. but wow only 500W usage for a single 590?? sheesh.. i'm still happy with my 1000W PSU.

OMG, I hate PSU purchases, I.m very critical about Voltages. I just upgraded my Cooler Master 800W to a Corsair AX1200. I didnt like seeing my 12 volts drop when running benchmarks or Folding. Had to return first one to get one that had a full 12 volts at idle. the 3.3 and 5 are still a little short, why me. Anyone else have these problems, or am I just too picky?

What is the PSU required for the GTX 560 Ti 2win? Will 620W Seasonic do?

CraptacularOne

Glad you guys like it. Also if anyone is interested, I can put together one for the 400 series, but not sure if there is a need for it anymore.

Coudl be useful as its still a very popular card as it comes out on sale alot nowadays

Well I'm at the in-law's house and the wife and her sister are off shopping today so I'll go ahead and throw together a 400 series PSU thread
 
EDIT: it's up here:
 
http://forums.evga.com...02&mpage=1#1342002

jimmycricket

so running a i7 960 2 gtx570 and 1 gtx470 my ax1200 should easily handle them all and overclocked

 
Yes.

Wow, just wow. I have been searching for about a moth for this guide. Probably serves me right for not joining the forums till yesterday. 

hmm not funny reading hehe now i realize i have to get a bigger psu hehe btw thx for this post cool thing to do

Well, I still have my old tried and true HX620W of about 5 years, and still running strong.  It survived the HD 5850 that was in there now, a 9800GTX+ before that, and an 8800GT before that...so I don't see why it couldn't handle a GTX 580 or even the upcoming GTX 680.  We'll see how well it'll hold up.