You could check the graphics card is seated correctly. Bad contact, which gets worse with a rise in temperature, often causes problems.
Failing that, you might have a conflict of software that is causing problems. Go to 'msconfig/services' tick 'Hide all Microsoft Services' click on 'Disable All' then 'Apply' then 'OK' and restart. Run your game and see if the problem recurs.
If you go online you will need to enable your AV/malware protection.
To reverse the setting do the same as above but select 'Enable All'. You could also seleclectively disable programs to determine where the conflict (if any) exists.