The maximum actual core temperature is 80C to 90C. What reading you see in the BIOS or in monitoring software is going to depend radically upon what motherboard you have, and how it estimates the temperature. Take the same CPU and heatsink, put them on an A7N266-VM and you might see 40C. Put them on an ABIT NV7M and you are going to see about 70C. But the CPU itself is at the same temperature, either way.
While many boards monitor the internal CPU diode, there are only two consumer boards (that I'm aware of) that actually do report temperatures directly from the CPU core to the end user: the EPoX 8KHA+, and revision 2 of the Gigabyte 7VRX/P. If you have one of those, typical REAL temperatures seem to range from 55C to 70C under load depending upon the cooling solution.