FSX doesn't seem to like my new clock

All tests, Occt, Memtest, PI - show a stable clock. Have NO issues with any other programs.
Run FSX as I normally do and within 2 or 3 minutes of clicking fly now I get a semi freeze. Meaning sound is fine but screen freezes and blinks every 10 or 15 seconds. If I hit ESC and wait a minute or two I'll get the end flight screen and after another 2 or 3 minutes I'll be able to exit FSX and get back to the desktop where things seem normal.
In the past, this is the same actions that I get when I try a new driver and it doesn't work.
BTW 3dMark ran fine and showed 12292 with defaults.
As I write this I realize that after changing the mobo, I did not uninstall,clean and reinstall the video driver (174.74) so I will try that first. I did remove the clock on the video card and am running default now - same problem.
My vCore is 1.28675 and nb is 1.51097.
After reinstalling the driver I assume that I should kick up the vCore and try again or should I try the NB first?
Thanx,
Vic
Run FSX as I normally do and within 2 or 3 minutes of clicking fly now I get a semi freeze. Meaning sound is fine but screen freezes and blinks every 10 or 15 seconds. If I hit ESC and wait a minute or two I'll get the end flight screen and after another 2 or 3 minutes I'll be able to exit FSX and get back to the desktop where things seem normal.
In the past, this is the same actions that I get when I try a new driver and it doesn't work.
BTW 3dMark ran fine and showed 12292 with defaults.
As I write this I realize that after changing the mobo, I did not uninstall,clean and reinstall the video driver (174.74) so I will try that first. I did remove the clock on the video card and am running default now - same problem.
My vCore is 1.28675 and nb is 1.51097.
After reinstalling the driver I assume that I should kick up the vCore and try again or should I try the NB first?
Thanx,
Vic