So I did a double session today. I quick benched 2 FX-55 San Diego CPU's.
Both CPU's could still boot 2400MHz at -130C (no MHz scaling beyond -95C):
FX-55 0516 WPMW
Max validation:
3906MHz
This CPU could still improve as I did not get the change to find best temp and voltage for that temp. It got worse results after 2 hours so I decided to go on with my 2nd session.
FX-55 0524 CABNE
Max Validation 3800MHz
Cinebench test run on Win XP 32b and 100MHz C2:
It crashed with opening CPUz.
What I learned so far about LN2 and San Diego:
- Cold Bug Post: Good CPUs can post -100C to -130C.
- Ideal bench temp: Seems to be between -80C and -95C. No more scaling in CPU max MHz after that. You can test this easily with Max multi MHz boot.
- Ideal bench temp: Beyond the ideal temperature (colder than...) the CPU scales worse in max MHz.
- Ideal voltage: Test it's proper voltage because you can easily validate 50-80MHz more by setting a lower or higher voltage. You can test this with Max CPU MHz validation.
- Max validation minus 100MHz, looks like: Cinebench 11.5 / PI 32M run Ok.
- Max FSB on good CPUs range: @-60C 310-325MHz // @-80C 270-290MHz // @-110C 230-250MHz.