Radeon 9000 and 8500 = pretty good, will play almost all recent games, but expect to have to upgrade within a year or so if you really like to game. The 8500 is slightly better, but only very slightly so get whichever's cheepest. There is a Pro version of the 9000 which is better than the non-pro. There is an LE version of the 8500 which is not as good as the 8500. I would recommend that you stay away from the non-pro 9000 and the 8500LE (unless you like to overclock).
Radeon 9500 Pro = Very good. Comparable to the top of the line gforce cards. Will run all current games and at least the next years games. It's fairly future-proof. Beware though, as there is a Radeon 9500 non-Pro which is nowhere near as good. You need the pro version, as the non-pro has been crippled in several areas (not just clock speed).
Radeon 9700 = Top of the line. There currently is nothing better out there. It trounces the compition, but has a very hefty price tag. It'll last you 2 years or more. Once again there is a non-pro and a pro version, but both are excellent, with the pro being better than the non-pro.
Also, the 9500 (both version) as well as the 9700 non-pro are just now coming to the market. They aren't widely available yet, and won't be for the next couple of weeks.
Recommendation: If you play alot of games and want the best bang for your buck, get the Radeon 9500 Pro. It's currently about $200 but will drop to about $150-$160 by December.
If you don't play alot of games, then get either the 9000 or 8500. They're both under $100. If you don't play games much or if you don't play recent games then you can also consider the non-pro or le versions.
If you don't play games at all then you can also consider the 7500. It's no good for gaming, but very good for everything else (internet, MS Office, Solitaire, etc). I wouldn't go below the 7500 though, as drivers for the 7200 and lower are not very good.
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