.... but on WinMe and AMD K6-2+ @ 600MHz!
I've found out that uninstalling the directx 8.1 and installing the old directx 8.0 allow Need4Speed (porsche unleashed) working again.
It seems that the problem look like the WinXP and Athlon XP problem.
I've the feeling that the "Power Now!" technologie is the "matter".
Any similar expérience?

Power Now isn`t part of the K6-2 ... so this should not be the problem

Need for Speed 4 dosn't have any official support for WinXP and it's a pain in the **** to get working on any OS past 98. Did you try installing the patch for NFS4 buried somewhere on EA's site?

Also you might have to try software mode, or some unofficial fixes if you have a non-3dfx card.

http://www.ntcompatible.com usually has some ideas on getting stuff like this to work on XP.

I was having problems with dx8 stuff quitting to desktop so I installed the M$ patch and then directx 7 games started quitting to desktop but dx8 games were ok. So I uninstalled the patch and voila dx7 and dx8 games are both working perfectly.

Try going to the shortcut for the game and right click - properties

There will be a compatibility tab - just set this to 95 or 98. I got colin mcrae rally working like this.

I think that removing the file gimme.dll in your Porch Unleashed directory will solve the problem. Try it!