Since the past 6 months i have been using my PC using my onboard graphics which is HD4200 (must be ATI), but prior to that i used to have my GTX 460 installed in this PC but it was on a 32 bit windows 7.
On 6th Sept 2012 i re fitted my GTX 460 with the latest drivers of that day ( first i uninstalled the ATI drivers from device manager and then used driver sweeper in safe mode) but soon after installing the GTX in 5 minutes got a BSOD but all i could see was a percentage counter like 0-5-10-15... 100 and a reboot. All this happened in 5 seconds max i guess. I reformatted the PC and this time installed the previous WHQL drivers from nvidia namely 295.xx something but they didnt work either.
All i had left to do was to remove the GPU and reinstall the onboard drivers and without my gpu pc worked great.
On the 18th i retried the experiment and it worked for 2 hours, even played heavy game on it and used the PC as i normally do and had no issues. But after 2 hours not even playing just seeing some images on HDD and bang another BSOD. SO i removed the GTX once again and its been working fine on onboard graphics since then. This GTX had been working very good for the past 2 years without a single crash or anything and then i simply removed it and kept it safely. Only thing between this was a shift to 64 bit OS, all things other than that are still same. I have explained the story as best as i could and i am still OK with my onboard chip but want to play some games as well in spare time but why this BSOD is beyond me, hence i come to you fine people for some help. The dumps have been attached as the forum asks for.