My brother wants to play Doom2, but for a reason I have yet to figure out, he can't play with sound or the game slows down. It's a Hewlett Packard something or other, 2.4ghz P4, sound/video drivers are updated, running WindowsXP Home w/sp2. Compatibility mode failed me. 8(

If anyone knows any tricks off the top of their head, would appreciate it.

Bit of overkill... but you could prolly run VMware and play through it, chances are he'll get bored of it before the 30 day trial runs out

Try playing with zDoom, or any of the other ports of doom that are made to run on recent machines. There's even a complete 3d remake of Doom, I have no clue how it plays tho...

I finished Doom2 recently using zDoom, had no problems whatsoever.