Spec says its max temp is 70'C.
Under continuous 100% load the temps should stay below that to prevent damage or degradation.
Add to this a safety margin and it should be about 55-65'C max.
Check the Vcore(CPU voltage) in BIOS, if you are not overclocking, you can lower the vcore a notch or two.
X3 8650 details @ AMD
X3 8650 details at CPU world
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