In terms of Performance and Driver support the crown goes to Nvidia. A GeForce2 Ultra or GeForce3 are still currently the fastest and most supported cards out there. If your looking to buy right now the card with the longest lifespan is the GeForce3. Hercules, Leadtek, Visiontek cards can all be trusted. There are some others but I cant speak from experience. Good thing about Nvidia is that there are a large array of drivers to pick from. Most are leaked and not supported but they crank them out almost biweekly.
ATI wins the great price for a kick-ass card award. Plus you will recieve the best image quality compared to a Nvidia card. ATI also has the absolute best DVD playback capabilities out now. For gaming this card is no slouch either. It acually performs better in 32bit color than 16. Also ATI's TV out features are also of a higher quality.
Here is a breakdown of some prices of these cards I'll list them in terms of the greates performer on down:
1. GeForce3 $350
2. GeForce2Ultra $260 Unless you want the Hercules Card
3. Radeon64 ViVo $175 ViVo is Video-in Video-out
4. GeForce2Pro64or32 $145-160 Just stay away from the Leadtek32MB version
5. Radeon32DDR $110
6. GeForce2GTS $120
I'll stay away from the sub 100 range for now.
I cant comment on Customer service. Usually that is left up to the dealer. 90% of your support will come from other users trial and errors. Both cards have excellent fan based websights that will provide better support than any company would. The edge in fanbased websights goes to ATI however.
My rankings on the cards performance may be off but just search some of Tom's video card articles.
Good luck.
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