Ok, which card is best for Linux, one with an Nvidia chipset or one with a Radeon chipset? Which one is easiest to install and which one has the best support?

Personally, I think Nvidia has pretty decent support. The drivers have been out for a while and they are very stable. There are also some good configuration utilities out there for Nvidia cards. I have never tried to use a Radeon card in linux but I've heard that the drivers are still a bit buggy. Plus Radeon cards aren't as good (at the risk of starting a flame war) unless you have a lot of money to spend on a 9800.

I think that I have to agree, seeing what others have had to go through to get things working. I use an ATI rage 128 pro, and I had to specify which driver to use so I could get 3d accelleration (otherwise it defaulted to the wrong one) and this happened for any distro I have tested lately (and that's quite a few). I don't hear the problems with the NVidea folks. Dunno if its true or not. I could use the only one I ever bought - conflicted with my motherboard - so I never got to use my GeForce.

As far as which card is better overall, I can't say either (I think they're both excellent), but it looks like the Nvidea's are easier to install than the newer ATIs (the older Radeons aren't so bad to install)

Simple, ...IMNSOH
Ati has the better H/W ...$ for $
nV has the better support under Linux.

I dropped a Rage 128 Pro from my Dell into my Mandrake 9.2 box and it worked from the git go. I think it really depends on the distro.

If you are talking about modern hardware, then I'd go nVidia. If you are talking old hardware like ATI's rage chipset, then it doesn't much matter. Older stuff will be running off of the OpenSource DRI drivers.

I have an nVidia GeForce4 MMX and it has worked great since day 1.

Yes, I was thinking about a 128mb or 256mb card. I was also leaning more towards the Nvidia chipset as well. I just didn't know how driver support was for either. I have a 32mb GeForce now and I had to download the driver and kernel source to get it to work with Mandrake 9.2 DL edition. With the Power Pack it was installed automagically. I don't have any experience with ATI cards and Linux. I do know in Windows certain ATI cards can be persnickety on occasion.

You can probably get away with leaving your driver alone and just installing the new card... If you are running the latest nVidia driver. Of course, the nForce series might have a different driver...