Is this possible. Or should I sell the 275?

NB powersupply is 600watt so that will be a bit stretched at best

I wouldn't dare to do it!

Atleast 750W to be on the safe side even if the powerdraw is about 500W when running full speed.
Go for a Corsair or Thermaltake PSU , choose one which have atleast 2 x PCI-E 8 connectors and 2 x PCI-E 6 connectors to be absolutely sure.

//Vyper

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Addicted to SETI crunching!
Founder of GPU Users Group

I wouldn't dare to do it!

Atleast 750W to be on the safe side even if the powerdraw is about 500W when running full speed.
Go for a Corsair or Thermaltake PSU , choose one which have atleast 2 x PCI-E 8 connectors and 2 x PCI-E 6 connectors to be absolutely sure.

//Vyper

Sixhundred Watt (600W) is sufficient for both cards. Maybe 2 570 will draw
600 Watt. (My FERMI, GTX470 & 480 + X9650 @ 3.55GHz, draws 450-500Watt running 8
SSSE3x optimized SETI MB 6.03/6.08 and AP tasks!)

IMO, it probably will function, but I should put the 570 in and use the
LUNATIC's Installer v.0.7 and run 2 (or 3) WU's at a time.
Or FERMI compatible (stock?) app.

Both cards are quite different, in architectural way.
If you combine them, you can run only 1 WU per card, ofcoarse there will be exceptions.......?!

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You have a power meter to measure the wattage at the wall plug?


I would guess..
i7 860 - ~ 200 W (full load CPU, without GPU, but with all other stuff)


http://www.nvidia.com/object/product_geforce_gtx_275_us.html
GTX275 - ~ 220 W

http://www.nvidia.com/object/product-geforce-gtx-570-us.html
GTX570 - ~ 220 W

= ~ 640 W (full load CPU and 'power gaming' on GPUs - if this is possible with different GPU series)

If you crunch S@h-CUDA (AFAIK, my GTX260 OCs, 3/4 of max W usage):
200 + 165 + 165 = ~ 530 W


My PSUs are used ~ 50 % of the max.
So I would go in your case with a 1000 W PSU (for 24/7 crunching).

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You have a power meter to measure the wattage at the wall plug?


I would guess..
i7 860 - ~ 200 W (full load CPU, without GPU, but with all other stuff)

--[Snipped]---

Yes, when crunching only SETI, MB (4x 6.03 on CPU, 2x 6.08 on GPU's), it takes ~500-515 Watt. With 2 GPUgrid WU and 4 SETI MB, 490Watt.With 2 AP WU's it's
also a bit less, ~500Watt.
Measured between mains and PC PSU.

(CPU @X9650@3.55MHz)

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