I ran the memory test too comes with vista. it doesnt report any errors. I ran prime 95 for a bit long time and the pc is stable. but the temerature is very high, load temp is 90C and idle is 60C (maybe because i live in a country with the room temperature around 35C ?)
90 C under load?
You may need to pull the motherboard from the case to be certain that the heatsink is properly installed. You should also see what you can do to improve air flow through
the case, not just circulation inside it. And you may need to consider a better heatsink even if you are not overclocking.