Hi there,

I'm planning to upgrade my power supply in order to run two graphics cards for SETI@home and a few other BOINC projects. My current computer has a modular PSU, namely the Corsair TX550M (Bronze certified). The motherboard for this build is the GIGABYTE GA-Z77-D3H Z77 S-1155 ATX IVY, which does not support SLI for NVIDIA graphics cards.

Initially, I'm tempted to buy the Corsair RM850 PSU. Currently, I run SETI@home on the Gigabyte GeForce GTX 660 and I would like to buy an additional card from the sames series since it seemingly is very cost efficient and cool.

My questions are as follows:

1) Do I need to replace the power cables I currently have attached to my motherboard from the old PSU, or can I simply remove the PSU and keep the old cables for the new Corsair unit? If I could keep the old cables, it would be very easy indeed to upgrade my system.
2) Even if my motherboard does not support SLI, can I still run two 660s separately for BOINC GPU tasks?

I would very much appreciate any help you can give me.

Yours sincerely,
Ragnar

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Checked from my AX650: Corsair AX 650/750/850 have same cables (printed on the cable). AX1200 has different (printed "AX1200 only"). So you may have to use new cables that come with the PSU.


SLI is not needed. You can run the GPU cards separately.

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To overcome Heisenbergs:
"You can't always get what you want / but if you try sometimes you just might find / you get what you need." -- Rolling Stones

Boinc does not use SLI.

You can run as many video cards as you have PCI-e and PCI slots.
Physically fitting them would be hard, so using two PCI-e cards is best.

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If you don't mind ghetto look and duct tape, you can just use a separate cheap psu for the second card.

Use this http://forum.overclock3d.net/showthread.php?t=394 to activate the separate psu. Now your second card has power. Now turn on the pc on so your first card and your whole pc have power too.

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Thanks for giving me some advice!

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