Max. CPU operating temp for the Pentium d is 69.8 or 63.4 C - depending on which core you have, Presler or Smithfield (later).
You would be surprised just how hot GPUs run - max for the 9500 is 105 C!
A coule of useful sites:
CPU-World: Microprocessor news, benchmarks, information and pictures,
Maximum CPU Temperature | Hardware Secrets - sadly the latter hasn't been updated for about 4 years.
SD