0.95 year old problem. Known problem (check EU forums). Still no resolution. Still no promise for fix. Symptom: day before chapter 4 release (i.e. chapter version 3.xxx) it worked fine. day after chapter 4 release, it crashed.
Seems to be related to ALL agp cards, even the top end end-of-life $400-$600 cards, although Frogster EU won't admit as much.
OP, if it worked fine yesterday, but won't work today, the most likely suspects are either system update or corruption. I presume there was no update of system components during the period from working to not working, right? Things like DirectX update or windows update can go astray.
If not, likely one of the files in ROM itself got corrupted. Reapplying the latest patch sometimes fixes it (check manual update patch thread for details), but not very often. Pazuzzu's suggestions also worth trying. Otherwise, it likely will call for reinstall, sorry to say.