Hi fellow BOINC enthusiasts. I have an HP ML350 G6 server running Ubuntu that I would like to upgrade to do GPUGRD crunching, but I really don't know anything about graphics cards.

The server has one PCIe-2 16-wide slot that I believe is functionally only 8x, and one other 8x slot. I can't seem to find the specified 150W PCIe power cable for it anywhere online so I would have to use a molex adapter. It has a 1200W PSU so can probably handle a card okay. What I would like help with is 1. what's your recommendation for the best card I could run in it and 2. your recommendation for the best option under $150, since I'm on a bit of a tight budget. Used cards considered if you think they would be okay.

I also have an old Athlon machine lying around that has an MSI K9AGM3 motherboard with one PCIe-1 16x slot and a 380W PSU, plus I have a spare 480w PSU I could put in it, so recommendations for that would also be welcomed.

Thanks for reading my post!