it's only rational to go for a safe margin, knowing that most PSUs are not very good and have in reality an output below advertised; add that all PSUs do degrade performance over time and having a borderline PSU is asking for problems; in the long run most hardware failures (toasts) come from a defective power supply, that is known for fact, at least among ppl who do not mystify these things. but then again, everyone is master of his decision, as the risk is always on the betting side..

Quality PSU is always a must, I didn't advocate for crappy PSU.

However, having anything >500w quality PSU for one 580gtx is excessive.

Alright, time for empirical evidence.
My system is currently this:
4ghz i5 2500k (lowered the clock last night because I wanted turned some fans off for quieter operation).
570 gtx
1 90GB SSD
8GB (2x4gb)
1 120GB SSD
1 2TB HD
GA-Z68MX MB
3 fans running (in quiet mode).

Using Killwatt, I get this:
Idle is <80 watts.
Black death track on CloD never tops 280 watts

Remember this is wall draw, not output. It's efficiency is at around 90% at that wall draw, so the actual PSU load (using my sloppy math) is 252 watts. That means during gaming, the PSU is only at ~50% load. Average load would be even lower!

I think my system is running fine with a 40% margin buffer. If a PSU degrades that much within its life time, then it s a crappy PSU people shouldn't have bought in the first place.

What people should really doing is buying PSU that will give them the best efficiency given their components, and right now, for one GPU system, no more than 500watts (for a quality PSU).

Amen! Quod demonstrandum erat ... Thanks God I didn't "mistify things" ... ;-).

Have a nice flight mate!
Ins

take note:

Seasonic ss 460W - 160,55 €
CORSAIR HX-650W - 114,60 €

being Corsair a renowned brand and HX a professional series, it's worth noting that Seasonic ss costs way more while offering considerably less power; this happens because this given Seasonic PSU is one of the most expensive € for W in the market; so you can get away with it because it's absolute top of the line and, regarding it's output, extremely expensive as well.

this "it's their money and their choice" argument is a 2 sided coin; to give an example the Seasonic ss 460W offers the utmost efficiency and stability; a 115€ Corsair TX 850W, while not as good is a quality one and can SLI 2 GTX 580; the Seasonic cannot.

bottom line is, if you go for nothing but the absolute best then about 450W will suffice; go for a good mid-range and 550/600W mark, depending on quality, is perfectly reasonable and recommended; go for entry series, 600W may lead to trouble (and above that as well)

p.s. - i just can't understand how someone could disagree on this, especially if they have a GTX580 and 550W PSU on their sig...

Nice try to turn tables ... but I'm happy that we agreed, in the end. It is useless to go for a 750W, lest an 850W for a single GTX580. OP's CX600 was good enough.

Cheers,
Insuber

PS: BTW you cannot compare the prices of a fanless PCU with a traditional one ... ;-)

lol, as funny as this is one must let it drop eventually

cheers,
Raso

Hi, as a owner of a 480 and now a 580 overclocked I can say that I would strongly suggest against this, not only will you be pushing the limit with a standard clocked card it could pull excess power away from other needed computer hardware components (but never heard of someone willing to buy a 580 and not a decent PSU though).

Amen. AX1200 is on the way in prep for my planned duel 580 setup.

As soon as the 3 gig 580's drop a tad..I'll get one.they are about 570 US right now..that is pricey...wish I had known..as I paid 350 for my 570....which is not even 4 months old...wish I could sell it and put the money into the 580..:(

Try paying $400 for ram 1.5 years ago which now goes for $75 :rolleyes: