Could you please share how exactly you did it? I have a 4870, and I purchased a 9800GTX+ for folding. However, when I try to install the latest nvidia drivers, and a few versions back from that, it doesn't seem like they install correctly. I say this, because there is only one process running in taskmanager- nvvsvc.exe, "NVIDIA Driver Helper Service". Also, when I try to open the nvidia control panel after installation, I recieve a "This application has stopped working" message upon opening. So, could anyone who has done it, be of assistance? EDIT: I have the 4870 connected to one monitor, and the 9800GTX+ connected to another (with desktop extended to it). Also, the 4870 is in the first PCI-E slot, the 9800GTX+ is in the second. And, I know that basic vga capabilities work, because the 9800GTX+'s monitor has picture.