I'm not sure of the former, but I have the MSI NX8500GT pci-e card that I purchased recently and it works great in Linux Mint KDE CE. I had no problems with it being recognized. I bought this card over other versions because it has a heat sink instead of a fan. I have an Antec P180 mid-tower case I also bought, and with the three large platter sized fans in it, I don't need a fan on the graphics card. Plus, fans just generate more heat in my opinion. Some would go with a 8600 card, but I wanted one without a fan and a card that was under 80 dollars. Don't know if it matters, but my power supply is a corsair 550 W.
Edited to add, the fans are more like saucers than platters
Athlon 64 FX-57, Asus A8N-E, nForce4 chipset, video card NX8500GT GeForce, sound card bGears b-Enspirer w/ audio contlr: CMI8788 [Oxygen], 4G RAM, Sata WD hd 160G + 320G. Boot XP Pro nLite and a few other Linux distros.