Heh Staz. Another who still rates the 8500. It is the grandaddy of all the cards that came after at & if you look at all the functionality it introduced it is an awesome card.
gizmo - I would look at what you are trying to achieve. Since I would postulate the reason you are considering a gfx card is because you are trying to achieve some sort of framerate @ some quality setting in a particular game/ set of games.
You need to look at the relative perf. of those cards in those games.
Then rope in your budget & see what options are out of the question. From those left which gives you the closest to your desired perf. at the lowest price - or vice-versa, what is the highest specced card you can find within your budget (say on eBay for example - you may get lucky / you may get shafted too
you may want to give it a try this way).
If you are wishing to play Doom 3 then its simply a case of heading over to HardOCP for their detailed breakdowns of real world perf. with various cards/chipsets/cpu combinations.
If only they had done this for every major release - it is the data we all require when attempting to make our hard earned cash convert into the most guaranteed fps in our system for our desired games.
While discussing the 8500, it is a bit of a controversial option - but do look for a Ti4600 or Ti4800SE these are getting cheaper all the time & are again the top of the line cards of 2 gens back.
Go for 128MB versions of course.
The advantage with going nVidia is the potential for gaming on Linux. What games?
UT 2003/2004, ET etc. clients, I have been told run smoother on this OS (by someone who was dual booting Slackware / XP ).
As Staz put it. May the GPU wisdom be with you.