Windows 7 problemer med Display driver

jeg har på det seneste haft nogle underlige problemer med min Stationære PC, hvergang jeg startede et program (Chrome og PC spil) og det havde kørt et stykke tid ville dette ske:
1: billedet og lyden fryser
2: sort skærm
3: billede + rapport om at display driver stoppede med at virke
  men "recovered" igen
4: sort skærm
5: samme som 2
6: sort skærm
7: Blue screen eller complet frys.

den har:
windows 7 ultimate x64
Nvidia 9800gt
7GB ram

her er 3 rapporter fra Windows Log viewer (i rækkefølge
1:"Event filter with query ""SELECT * FROM __InstanceModificationEvent WITHIN 60 WHERE TargetInstance ISA ""Win32_Processor"" AND TargetInstance.LoadPercentage > 99"" could not be reactivated in namespace ""//./root/CIMV2"" because of error 0x80041003. Events cannot be delivered through this filter until the problem is corrected."

2:"Faulting application name: daemonu.exe, version: 1.8.15.0, time stamp: 0x4fb201e2
Faulting module name: daemonu.exe, version: 1.8.15.0, time stamp: 0x4fb201e2
Exception code: 0xc0000417
Fault offset: 0x000520c5
Faulting process id: 0x8c0
Faulting application start time: 0x01cd70bf47461c70
Faulting application path: C:\Program Files (x86)\NVIDIA Corporation\NVIDIA Update Core\daemonu.exe
Faulting module path: C:\Program Files (x86)\NVIDIA Corporation\NVIDIA Update Core\daemonu.exe
Report Id: 85602690-dcb2-11e1-925c-001921eb79fe"

3:The NVIDIA Update Service Daemon service terminated unexpectedly.  It has done this 1 time(s).

på bluescreen hentyder den også til en Nvlddmkm.SYS