I would say one of these, would give you good performance...

GF4-ti4200 to GF4-ti4800 or Radeon9600 to Radeon9800.

GeForce FX 5900XT. Fast, compatible, cheap.

Fastest possible with proper driver support would be either a Geforce 6800 Ultra or a Radeon 9800 XT although some later cards can be made working on it.

But as always the best is expensive.
Might look into something like:

• 6800 LE
• 6600 GT
• 5700 Ultra, 9500 Pro/9700 nonPro
• 9600 Pro, GF4 Ti 4400/4600
• 5600 Ultra, 9550, GF4 Ti 4200

Of course depending on budget. I'd go with a newer midrange card over an older high-end just for availability and price. Something like a 9700 Pro or 9800 will be expensive due to demand but a 9600 or 5700 will go fairly cheap.

go for a quadro fx 2000, its a geforce fx 5800, but it only costs $40 usd. (look at the sold listings for the fx 5800)
from what ive heard, the geforce 6 series doesn't perform as well as the fx series in older games.

For windows 9x:

Nvidia Geforce 5950XT or similar card is the best, or ATI 9800 PRO/XT.

The 6xxx series cards from Nvidia do work in windows 9x, and they do seem to be faster even on the old machine, but the drivers available that work on this series of card are not that good with for win 9x. They are better for an XP system.

I would advise not to use any FX 5800 or Quadro counterparts frequently (gaming rig). This cards are very fragile and hard to come by due to all that youtube hyping. Good for collecting though.

bjwil1991, for your system and OS I would stay between a Geforce2 GTS and ti4600. With driver versions around 28.xx or 30.xx you will get peak performance, depending on what resolution you play at. Also, try to limit AA to 2x, as 4x will murder this range of cards. Phil made a video about this topic - very informative.

The Serpent Rider wrote:

I would advise not to use any FX 5800 or Quadro counterparts frequently (gaming rig). This cards are very fragile and hard to come by due to all that youtube hyping. Good for collecting though.

the quadro cards are still relatively cheap and easy to get.
however, the 5800 sells for multiple thousands of dollars/whatever other currency

My absolute favorite is the Gainward Geforce 4 Ti 4800 SE.

It is very overclock-friendly and can run at a higher clockspeed than a regular 4800 non-SE card:
http://www.legitreviews.com/gainward-ti4800se_7

the quadro cards are still relatively cheap and easy to get.

This well will dry up pretty quick.

The Serpent Rider wrote:

the quadro cards are still relatively cheap and easy to get.

This well will dry up pretty quick.

oh yeah that's true for almost everything

mmm Ti4200