So I'm running Ubuntu 12.10, and I use Linux exclusively on all my machines because I prefer it, and don't really have a need to have Windows installed.
Lately, especially since the release of Steam for Linux, I've been using my Ubuntu desktop PC for more and more gaming on Linux, but I've had one issue. For most of the games I have, including a lot of older 3-D games, my on-board AMD graphics card with the open source drivers works fine, however it is old enough and low-end enough that AMD doesn't support it any more with the Linux version of their driver.
I'd like to pick up a more powerful video card that actually has Linux support from the vendor. I don't play anything that really needs the latest and greatest video card in production, and I'm not really interested in spending a week's pay on a video card, although I do have some games, like Penumbra: Overture, that I'd like to be able to play with particle effects and stuff enabled. I don't really care whether it's NVidia or ATI, as long as it has native drivers for Linux and works well in Ubuntu.
Anyway, I can build a PC, and I'm pretty handy with installing and configuring any piece of software you give me, but when I talk to some of these, what I call "hardware geeks", and they start throwing numbers at me, I feel like a noob all over again, so I'm fishing for suggestions from all you hardware gurus out there.
What do you think would be the best video card for my situation? Let's assume there's a $100 limit on price, what would give me the most bang for that buck? Here's some information on my current setup.
Processor: AMD Athlon™ II X2 220 Processor (Dual core, 64 bit, 2.8 Ghz)
Memory: 4 GB RAM
Graphics: ATI RS880 (Radeon HD 4200) <-----On-board
OS: Ubuntu Linux 12.10 64 bit







