XP can run dos games? Does the sound work?
I am using ME and actually get the opposite problem in many games. The original Descent runs way too fast to be playable (the rate at which your ship bobs up and down makes it look like an earthquake), although the D1_3dfx version works very nicely. ROTT and Dark Forces also run at insane speeds. Doom 1/2, Duke Nukem 2, Raptor, Skyroads and some others work fine though. Descent 2 is okay but I have to put in on the maximum resolution and turn off the cockpit to slow it down enough to be playable, or else it is like D1. The main problem is that I haven't been able to get any of the SBLive's SB16 emulation to work since I upgraded the motherboard, so there is no sound in most of the games.