You have a good heatsink, so I would look at case airflow. Intel cpus are pretty tough with temps. I ran my old northwood at up to 72c in the summer when the a/c wasn't running. It has outlived 2 motherboards. Under load, those quads run pretty warm. I hate noise, so I put up with high temps. Watercooling is another solution, but ocasssionally, those setups leak causing component failures.
If temperatures increase beyond Hot Scale, then ~ 5c below Tjunction Max, Throttling is activated. The Digital Thermal Sensors (DTS) are used to trigger Intel`s TM1 and TM2 technologies for frequency, multiplier and Vcore Throttling within individual Cores. If Core temperatures increase further to Tjunction Max, then Shutdown occurs. Since Tcase indicates CPU Die temperature only, it is not used for Throttle or Shutdown activation, however, Tjunction Throttle temperature is ~ 95c, so Tcase would be ~ 85c, which would far exceed Tcase Max. As Tcase to Tjunction Deltas are constant, Tcase Max is always the limiting specification for temperatures.
Scale 2: Quad
Q6x00: Tcase Max 71c, G0 Stepping, Tjunction Max 100c, Vcore Max 1.372, TDP 95w, Delta 10c
-Tcase/Tjunction- --70--/--80--80--80--80-- Hot --65--/--75--75--75--75-- Warm --60--/--70--70--70--70-- Safe --25--/--35--35--35--35-- Cool
Note 3: SpeedFan is very flexible and is the temperature monitoring utility of choice. SpeedFan detects and labels thermal sensors according to various motherboard, chipset and super I/O chip configurations, so the Tcase label can be CPU, Temp 1, Temp 2, or Temp 3. Even if Tcase is labeled as CPU, it is still necessary to confirm the identity of Tcase prior to conducting Calibrations. Run Prime95 and note which SpeedFan temperature scales with an Idle to Load Delta similar to the Cores. This will identify the label corresponding to Tcase. Labels can later be renamed using the Configure button, (see Section 11). If a temperature shows a flame icon, this indicates alarm limits which require adjustment. Use the Configure button to set CPU and Core temp alarms to Safe Scale. If a temperature shows Aux 127, this is simply an unassigned input which can be disabled using the Configure button. CPU`s with Steppings which are Tjunction Max 100c typically require +15c Core Offsets. See Section 11.