f12000cs demo problem

I finally downloaded the demo and installed it, but the game hangs when i reach the main menu (i need to do a hard reset of the computer). What's the problem???? I have � Celeron 400 OC to 500, V3 2000 OC with no problem elsewhere, latest 3dfx drivers 1.07, 64 Mb ram, DX8. Any ideas??? I have remarked also that i can't use my mouse in the Superbike 2001 demo (same editor as f1200cd, EA). Is it related, that's the question!!! Thnax in advance;