Upgrading old motherboard GPU

After seeing that I’m way under powered in the GPU department (47 minutes for the render from the cycles benchmark thread) I’m considering upgrading the GPU in my Windows PC box, but not sure about the details.

The motherboard is EVGA 122-CK-NF68-A1 LGA 775 NVIDIA nForce 680i SLI ATX Intel
I’m not sure if the NVidia GFX 660/680 boards will work with it. I’m looking at about $200 for the upgrade.
Also, the PSU is 700W.
Any suggestions?

Hi, your board have 2 x PCIE x16 slots which are suitable for GTX 5/6/700 series.
700 Watt is also good for one big card.
May you look for a used GTX 5/670 4 GB, I would not buy cards less than 2 GB depends on your work style.
The GTX 500 are faster than GTX 600 but are hotter and need more power.
Here is my last benchmark chart:

http://www.blenderartists.org/forum/showthread.php?303832-New-Cycles-Benchmark&p=2511896&viewfull=1#post2511896

Cheers, mib.

Thanks mib,

That’s good to know about the GTX 500 units.
The chart is a good way to determin which units with which OS give the best results.