Users of Intel Core 2 Duo processors please be aware that temperature's of 85C are not acceptable on the processor core, neither on the CPU installation socket.
With Core 2 Duo the sensor that is detected is the on board socket sensor. This temperature (depending on system configuration) will usually be about 10C lower than the actual on die temperature.
To determine your CPU operating temperature (Core) please use the Intel Thermal Analysis Tool. This application has the ability to receive data from the CPU core sensors for both cores, this is very accurate (unlike most sensors). This is because the algorithm is more sophisticated
Intel Pentium 4 processor default sensors are on die, Core 2 Duo are not. Due to this fact people are getting confused between temperatures.
Rated Operating Thermal Level of Intel Core 2 Duo processors is 60.1C, this can be acceptably breached if voltage is within a certain range of default.
A temperature of 85C will be causing very slow damage to parts of the chip. However the shut down temperature is measured using the onboard sensor and therefore will not shut the system down unless the socket temperature breaches about 66C.
A custom BIOS may allow the system to switch to the "on die sensor", then your system would not boot/operate if it's processor temperature is at 85C
These processors are not the equivalent of Core Duo/Dothan which are designed to operate at up to 100C