Hello Al Hill thanks for your reply,
-I am not overclocking it and run time of my CPU is hardly 4-5 hrs, so i think a stock fan would be adequate.
-And yes there is adequate amount of air intake.
Now coming to power supply, its the only component left unchecked till now in a corsair service centre.
-But the PSU which the gigabyte service centre engineer was using behaved in the same way as my PSU did, when he put in my processor in the mobo.
-As you said to replace the power supply, the same suggestion was given by the gigabyte service centre engineer to get it checked at the corsair service centre.
-But i have doubt that my PSU might be at fault because it had worked perfectly after i got my CPU repaired under warranty.
And if my PSU is at fault can u please explain, how it might be damaging my processor and that to after some specific period of time.
One more thing i forgot to mention is that, the failure of CPU occurred on both occasions when my computer was not turned on,
Like i switched it ON in the morning the whole system worked perfectly, i turned it OFF perfectly but when i came home in evening it just didn't start.
What I am now thinking is that you may have a "cold joint" on the motherboard. By pressing around the areas that I suggested it may cause an open connection to [temporarily] work.
If doing this method produces any results, you would need to replace the motherboard.
This is just a guess. I could be completely off target here.
Personally, if the system was still under warranty, I would have the whole thing replaced.