Whats the ambient temps in the house? That can add to the temps? If its 80 degrees in the house, it cant cool the PC that well. If possible, try turning down the temps.
Also try turning up the fan speeds, and like Remeniz said, clean the heatsinks, the CPU reapply thermal paste. Take out the videocard, remove the heatsink and clean it and the GPU and re apply thermal as well. See if this helps.
Also, is this CPU or GPU overclocked?