hi trotter!!!thanx for suggestions.
i built my PC half year ago it should not be very dusty inside,but i'll try -it might help.i have read so many stories about not properly installed heatsinks ,burned thermal pads and burned processors and so on...
by the way my case is BeanTech full acrylic (maybe that...?!?)
p.s. now i can play only online quests in only text ,but man-it rocks(i love quests)
p.p.s my idle PSU temp :53 C mobo abit 3rd eye