Minimum psu for 2 8800 ultras?

[FreeStream]

That a constant or peak? most PSUs are rated for their peak power output... for 350 watt constant you'd really need a 500 watt PSU.

Ummn, no.

My OCZ 520W is 520W constant 600W peak...
My Seasonic is 600W but probs has a 700W peak.

SO I could run 590W 24/7 easily

 

[Raikiri]

Measuring from wall...(Same as Jokester)

So your power draw is closer to 320w then accounting for the inefficiency of the PSU.

I am guessing you're running about 3.6ghz and have the GPU at near Ultra clocks?

 

[chaparral]

So your power draw is closer to 320w then accounting for the inefficiency of the PSU.

I am guessing you're running about 3.6ghz and have the GPU at near Ultra clocks?

Yes and yes

 

[Raikiri]

So to be fair, you probably could run a clocked quad core and overclocked Ultra SLi just about on your PSU, at stock they should be fine with the 620w corsair.

Just wondering because I am sceptical of the accuracy of the Zalman fan controller when it comes to measuring power draw. A slight bump in clock speed and 2 extra cores at most is going to add around 100-120w unless he is running pelts as well from the PSU.

 

[fornowagain]

But it's only using one 8800 Ultra
And it not worth running SLI 8800 Ultra's without a quad CPU..

873W, approx 715W at the psu. Of which approx 85% is at 12v or 607W. Most of the cpu and graphics is 12v. From Jokesters system, QX6700 130W TDP @ Stock, 2660Mhz, 1.275v. (TDP's maybe 10% less than the max as well) @3.5 Ghz, 1.50v approx 235W . The overclocked Ultra with a voltmod, stock TDP is 170W (less used at stock), maybe 190W. Can see the rest of the system, pumps etc, using the remainder.


This is a good example, and that's with a power sucking 680i.

http://www.behardware.com/art/imprimer/670/

- ASUSTeK P5N32-E SLI Deluxe (nForce 680i SLI)
- Intel Core 2 Duo QX6700 @ 3.2 GHz @ 1.5V
- Ventirad Scythe Infinity
- 2 x Albatron GeForce 8800 GTX
- 4 x 1 GB DDR2 800 @ 2.25V
- 2 x Western Digital Raptor 74 GB
- Samsung 250 GB + Maxtor 250 GB
- Lite-On CD-RW 48x
- Enermax 120mm at max
- Creative Sound Blaster Audigy

687.6W load at the wall.
567.6W from the psu.
82.6% efficiency.
85.3% of the wattage at +12V.

So that's a fairly top end rig using 40A/484W at 12v, a bit much for a 520W corsair, but easily within spec for the 50A 620W version.

That a constant or peak? most PSUs are rated for their peak power output... for 350 watt constant you'd really need a 500 watt PSU.

Most decent named brands are rated at continuous power and held at a high temperature, usually 50C. PSU's derate 20% for each additional 10C, so a 500W at 50C is a 400W at 60C. Cheap and nasties are rated at peak values and low temps.

 

[Sean_UK]

at stock they should be fine with the 620w corsair.

Glad someone agree's with me at least.

 

[Cartho]

2 ULTRAs?
I would suggest having a nuclear power station wired to your house might be adequate

 

[ChrisD.]

Another one to look at could be the Enemax Series, again rock solid PSU's. You get what you pay for