If you ever intend to use Linux, nVidia is the way to go. ATI’s Linux support is pretty bad, I hear. I’ve never had any problems with nVidia cards on Linux (even 64-bit Gentoo).
In my experience nVidia’s Windows drivers are better than ATI’s as well, although I haven’t used an ATI machine for a year or so.
nVidia seems to be more standards compliant, but I’m not well educated in that area so take that with a grain of salt.
My general impression has been that ATI is about flash and fancy bells and whistles, whereas nVidia is about performance, stability, and compatibility. ATI’s are great for games, but I’d go with nVidia for anything else. (Again, take this with a grain of salt… these are just general impressions I’ve gotten over the past few years.)
I have a Gigabyte Geforce 6600 256MB. It runs like a dream. I can run Quake 4 on ultra high with 1024768 shadows, high deffinittion effects. And still get a frame rate between 20-63.
On medium quality with with a resolution of 1024768 its round about 35-63.
Same with Doom 3.
Only thing that is slowing my pc down is the amount of RAM (512MB 400Mhz) and the processor(AMD 2100+ 256kb 1.7Ghz). More of the RAMslowing the pc down than my processor tho.
Remember the pc runs as fast as the slowest component.
@kit89: Nice Graphics card! You should pick up another 512MB of DDR RAM off eBay and bump it up to 1GB of RAM, I did that myself the other day, only cost me £20 and it makes everything run much smoother. (I have an AMD 2100+ too )
From my experience, I dont really think one company is better than the other. I used to have a geforce fx 5200 and never had any trouble with it, other than it wasnt that powerful. Recently I upgraded to a Radeon x800 GTO, so far it has given me no trouble with blender and has been great with games(plays FEAR and call of duty 2 on max with great frame rates), thus I dont think you can really go wrong.
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