XP random restarts but not in safe mode

Hi, I am new to the forum so be gentle

My recently started experiencing random reboots and eventually registry corruption (assuming due to the random reboot as windows did not shut down properly. it was as if the machine was unplugged suddenly).

System Specs:

Dell Inspiron 530
intel core 2 quad 6600
3gb Memory
ATI Radeon HD 4550 gpu
462 gb samsung SATA hdd

Symptoms: System reboots with rarely a bsod and always no warning, just suddenly screen goes black and system reboots. I have determined it only does it when when running video or games that require flash. mostly facebook games. i have also determined that safe mode works on the games / video that cause the reboot in normal mode so i am assuming it is software related although I have ran numberous hardware tests.

What I have tried:

Restored machine to factory software (dell pc restore, not system restore as rstrui failed on every attempt)

ran memtest86 with no errors

ran chkdsk /r, ran chkdsk with no errors in either case

pulled the ram chips out and rebooted with only single chips. successfully ran with all 4 but I could recreate the crach on all 4 by opening a facebook game using flash.

pulled the video card out and used onboard video, still crashed


In Progress:

I am trying to get the machine to boot in normal mode with the same minimal driver set that is used in safe mode, confirm that I do not have the error and then start loading drivers one by one until it crashes again to identify the problem driver/service.

I have used msconfig to get to a clean boot state but still get the error. does anybody know how i can only load the drivers that are loaded in safe mode?