No, CPU PLL won't kill CPU if kept under 2V and for sure it won't kill it if around 1.88-1.89. It actually helped many to gain stability.
And you are right about other stuff.
Never mind the PC Probe, it tends to make such mistakes. Use 3rd party SW like RealTemp, HWMonitor, AIDA64 and such.
You might try BIOS
0095 (newest),
0096, or
0011 for Gulftown.
Start by dropping PCI-E to 100-105 and try CPU PLL range of 1.2-1.6V
And, yeah, use updated LinX from
Intel 4.5GHz & 5GHz LinX Stable Club. See the GFLOPS rise.

And temps BTW.

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