My CPU temperature (according to ASUS PC Probe) has suddenly jumped from normally running around 55 degrees C up to 70 degrees C. This has set off an over temperature alert. I've tried tried re-applying heatsink paste on the CPU but that hasn't helped. Any thing else I can try? The rest of the system is running cool and the motherboard temp is reported as 39 degrees C. My CPU is an Intel Core 2 6600 @ 2.4GHz.