I voted for ATI ...but i have Nvidia card
..its not that i dont like Nvidia , its just that ATI can have more reliable cards , even the lower range cards have their "big brothers" options , like x16 AA and stuff.. they perform better rendering and the texture looks much sharper (compared to FX 5 series) mainly because in Nvidia cards the textures are set not to very high ( u can tweak it , but im doubt u get the same image quality as ATI's) which in ATI its a defult .
But Open GL games will run better on Nvidia ( at this time..) cards , and on some games Nvidia will work slightly better then ATI ..on games that designed for Nvidia software ( not all ) .
The good thing a bout Nvidia cards its that you dont realy have to buy a new card when ever a new game hits the market
and im not talking about some 3D "pac-man" ...i mean real demanding games because of the drivers ..which most of you said they are crap ..but i found them very improving !
they bring all the new stuff from the "big boys" ( FX 5/6 ) to the old cards ! and makes them run almost the same , with the same options i recently found out my card is capable of having x8 AA ( which was not installed in the original drivers ) i have a Geforce 4 TI 4200 with 64 MB DDR ram runing on 251/513 hrz core and memory , NONE overcloked ! and every time a new game hits the market my card can compete with it very well! ( HL 2 has been tested on it , and works beautiful) . or you can say that all the new cards are simply an upgrade to an old one :P
In (rather miserable) conclusion :
The ATI cards shiped with all the "good stuff" turned on and modified for best performance ..while Nvidia cards come with more or less the same power , but with some lack of performance , but u can tweak it to get better performance :thumbup: ..but there are cards that can easily beat an ATI , but like i said ATI can be more reliable .
Note : none of the things i said come to harm Nvidias hardware .