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just removed all the dust, system temp now 28C, cpu temp 48C, I dont have a case fan so when I put side panel back on the temp went up slightly so with an external fan on it the temp went back down to normal, now running a film and the cpu temp has gone up to 60C with cpu usage at 30%, the pc is less than 6 months old,
intel core 2 duo E7200 1066FSB
asus p5n73-am skt 775
guess a good internal fan will make a difference but I dont know if these temps are normal for my cpu anyway