intel DG31PR 2.93GHz temp at bios 84c on starting - reason ?

[SUBHRO_1]

Intel DG31PR mobo with intel core2duo 2.93Ghz having thermal shutdown and temp at bios showing 84c at starting. I have changed the CPU fan and applied new thermal paste which resulted in running the PC well for 1 day only.then again the same issue. Could it be something related to the BIOS ? Kindly help. the PC is about 3 years old. I have checked the North and South Bridge and they seems okay.

 

[Pentium4User]

some mother boards/bios manufacturer make there cpu run at a hundred 100% in the bios that what I heard from some people.