Re: PCI slot solution
Concerning the 256MB does nothing comment. Most of the time now days a PCI card only has a 64 bit data path unless it's filled with 256MB and then it moves to a 128 bit data path, so because of that 256MB does help quite a bit.
It's true that normally 256MB would be wasted on a PCI graphics card but since they always seem to stick a 64 bit data path on any PCI graphics card that's not filled to the max with RAM then 256MB does help performance.
I upgraded my sister-in-laws DELL system that only had a PCI slot with a 128MB 5200 and then traded it for the 256MB 5200 and picked up quite a few frames per second in a Q3A test run because of the wider data path.
But I haven't seen a 6200 that has a 128 bit data path so you may be stuck with a 64 bit wide path for that chip. It's too bad they don't at least give the PCI bus all the speed they can since at best it's pretty slow.
So I guess my only advice is to look at how wide the data path is and get one with a 128 bit data path if you can.