A question about the power requirements of a GTX285

[raynman68]

I am currently building an water cooled i7 rig built around the Asus P6T6 WS Revolution and 920 processor when my kids surprised me with birthday gift of an XFX GTX285. I have folded for the [H]orde in the past, but am currently devoting my energies towards WCG. Lately, I have been feeling the itch to get back into folding once again on the GPU side and I am now think 3 GTX285's under water would be a beautiful thing. The question I have is how much power supply am I going to need to pull this rig off. With 3 vid cards I am figuring dual loops and possibly dual triple rads on the video cards alone. I have listed the components of importance.

Intel i7 920 CPU
Asus P6T6 WS Revolution
12GB G.Skill DDR3-1600 RAM
2 WD 1TB Black HDD
1 Samsung DVD Burner
3 XFX GTX 285
2 MCP355 water pumps

With regards to power requirement suggestions over clocks will naturally have to be taken in to account. Thank you in advance for your replies.

 

[capreppy]

i am currently running exactly your proposed rig on a TT 1200W PSU. Both CPU (running WCG) and GPUs (running F@H) are heavily OC'd and i've not missed a beat with PSU. Plus it is 87% efficient.

 

[Zero82z]

A quality 1kW PSU would be sufficient for those components. Something like the Corsair HX1000 or Thermaltake Toughpower 1000W, or on the higher-end, the Enermax Revolution85+ 1050W would be an excellent option.

 

[jws2346]

Woah brother raynman68 I did a quick calculation from info I've mined from the Internet. According to my information the i7 CPU = 130w (stock, idle), the GTX285 = 183w (stock, idle) and the MCP355 = 19w (stock, idle). So when you add it all up (and in my case finish tying my shoe laces ) I get the tune of 715w alone for the components mentioned above. I agree with the previous poster you could probably get by with a 1000w PSU. I'm more inclined to think a 1200w PSU like brother capreppy posted. I think a PSU is a very critical computer component and in the case of one as large as 1000w+ a very expensive computer component. So , in a nutshell. I'd go with a 1200w PSU for the overhead and the less wear and tear on the unit.

Brother capreppy could you please post the "at the wall draw" (like with a Kill-o-watt meter or some such) I would think that would give you a true and accurate measurement of the total power the boxen draws

EDIT: Oops I've been corrected twice on my watt draw numbers. The numbers were the maximum wattage draw (I DC 24/7 and I don't know or even care what the draw is at idle on my boxen). Being an avid 24/7 DCer I was just using those numbers because I'm one of the ones that use the ole' "better to be safe than sorry" expression.
I still think with a computer the beefier PSU you have the better off you are, but like they always say "to each, his/her own" (thats why I have a separate PSU's to run my WCing pumps and fans. I'd spring for a bigger PSU, but I like the redundency of having two PSU's (my main PSU is a questionable OCZ 700w and my secondary PSU is a server EMACS Zippy 600w) I don't know the price difference, but I'd do take brother capeppy advice and go with a 1200w PSU of good quality

DCing for the CURE

 

[Kowan]

i am currently running exactly your proposed rig on a TT 1200W PSU. Both CPU (running WCG) and GPUs (running F@H) are heavily OC'd and i've not missed a beat with PSU. Plus it is 87% efficient.

That's the one I'd get if building a new box today.
W0133RU Nvidia lists it for both 280 and 285 Tri-SLI setups.

I tried adding a 285 in my second box (HX1000w) with with 2 280s and it wasn't stable F@H overclocked. Might have just been something on my end, but my HX1000w is happy running 2 280s and SMP 24/7.

 

[raynman68]

Thanks for the input guys. I was contemplating going with the HX1000 based on my past record with Corsair power supplies but was unsure because of the power draw of the 3 cards. although it has been said many times that the Corsair is conservatively rated at 1000W questions in my mind still remained. I was looking at the Thermaltake W0133RU as well based on its reviews. In the end I ended ordering the Thermaltake. I have used Thermaltake power supplies in the past and only had one problem with a DOA on a going out of business sale that they took care of promptly.

Capreppy, I caught a glance at your build log on XS,very nice indeed. I ended up picking up a couple of Systrin drive enclosures from Amazon for my drives as well. When I get all my parts, I will have to look at doing a build log as well.

Once again thanks all for the input.

 

[sirmonkey1985]

Woah brother raynman68 I did a quick calculation from info I've mined from the Internet. According to my information the i7 CPU = 130w (stock, idle), the GTX285 = 183w (stock, idle) and the MCP355 = 19w (stock, idle). So when you add it all up (and in my case finish tying my shoe laces ) I get the tune of 715w alone for the components mentioned above. I agree with the previous poster you could probably get by with a 1000w PSU. I'm more inclined to think a 1200w PSU like brother capreppy posted. I think a PSU is a very critical computer component and in the case of one as large as 1000w+ a very expensive computer component. So , in a nutshell. I'd go with a 1200w PSU for the overhead and the less wear and tear on the unit.

Brother capreppy could you please post the "at the wall draw" (like with a Kill-o-watt meter or some such) I would think that would give you a true and accurate measurement of the total power the boxen draws




DCing for the CURE

your numbers are a bit off for those being stock idle wattage..

 

[Zero82z]

According to my information the i7 CPU = 130w (stock, idle), the GTX285 = 183w (stock, idle) and the MCP355 = 19w (stock, idle).

Those numbers are actually the maximum rated load wattages, not the idle numbers.

 

[jws2346]

Those numbers are actually the maximum rated load wattages, not the idle numbers.

Oops, my bad Zero82z. I sure didn't mean to lead anyone a' stray Seeing as I DC 24/7, I don't know or care what my idle watt draws are. I'm one of the "better to be safe, than sorry" peeps and I've always believed a PSU was a very critical component of my boxen (especially running 24/7) and the beefier it was the better (it isn't strained or maxed out, that don't mean put a 2000w PSU on a P3) . I still believe in taking brother capreppy's advice and going with a quality 1200 PSU, but as they always say "to each, his/her own"

DCing for the CURE

 

[Tigerbiten]

The way I work out a PSU requirermemt is .........
2 x CPU wattage + 0.75 x number of card x Card wattage + Extras = Approx draw of system.
Then 1.6 x Approx draw of system = PSU power.
So 2x130+(0.75x3x180)+2x20 = ~700 watts.
1.6x700 = 1120 watts.
So I'd expect a 1,000 watt PSU will probably be just over 50% load and a 1,200 watt PSU will be at just under 50% load.

Luck ............

 

[Zero82z]

Oops, my bad Zero82z. I sure didn't mean to lead anyone a' stray Seeing as I DC 24/7, I don't know or care what my idle watt draws are. I'm one of the "better to be safe, than sorry" peeps and I've always believed a PSU was a very critical component of my boxen (especially running 24/7) and the beefier it was the better (it isn't strained or maxed out, that don't mean put a 2000w PSU on a P3) . I still believe in taking brother capreppy's advice and going with a quality 1200 PSU, but as they always say "to each, his/her own"

Well, saying that something is an idle wattage implies that the load wattage will be much higher. So your post basically implied that a system like that would use a tremendously greater amount of power than it actually would. The PSU is definitely a very critical component, but it also isn't necessary to go too overkill .

 

[jws2346]

Well, saying that something is an idle wattage implies that the load wattage will be much higher. So your post basically implied that a system like that would use a tremendously greater amount of power than it actually would. The PSU is definitely a very critical component, but it also isn't necessary to go too overkill .

I couldn't disagree more . Not with the 1000w PSU vs the 1200w PSU thing because I could honestly give a shite less . If someone isn't smart enough to use Google or some other Internet searcher to get the idle and load watt usage of a pretty well known computer componet than I certainly can't help them and neither can you. . (and I ain't talkin' just about the BS some manufactuers state, like the fan loudness crap )

Now, what I basically or non basically implied was what I got from thre manufactuers website The numbers may be at full load and may be the maximum draw, but I'd rather know that up front incase 24/7 DCing causes my computers to draw it's maximum wattage I think many others would also. I don't see using my computer at it's max performance as tremendously overkill. Whatever the f*ck that is. In fact I DO want OVERKILL and cushion when I'm pushing my electronics to it's max

The above post is only my opinions. If there is some disagreement I don't care, I don't think everyone agrees with everyone, at leasrt IMHO they shouldn't

DCing for the CURE

 

[Zero82z]

I couldn't disagree more .

I'm not really sure what you're disagreeing with .