You'll be able to play all of the games out now with pretty good graphics, but some of the FPS's might run slow. However, the games in the near future may pose problems, especially games like Doom 3.
It depends on what you play really. Some will work really well while others won't, depends on how graphic intensive each one is. In general, though, you won't be able to play with the best settings on any recent game.
Fortunately, by spending just a little more money, you could get a very good videocard and another stick of 256 MB RDRAM. If you can't afford it now, wait for the next generation of GeForce to come out in January or February (or wait longer for the next ATI), and all the top cards of the market now will be really cheap.
Even now you can get a GeForce 4 Ti4600 for around $200 - $250 if you look at different websites. You can get the best card out now (ATI Radeon 9700) for about $330 if you look in the right places, but I'm guessing you don't want to spend that much.
So my advice in two steps:
1. First buy another stick of RDRAM before anything else (and make sure it's the same kind as you have now)
2. Then sometime down the road buy one of the best cards of the market now when they get much cheaper
Since you have a very good processor and RDRAM is the best to have, that's really all you need to be able to play the games coming out in the next year or two.
db (deed bleed)
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