So you tried 1.44 in BIOS, or 1.44 real voltage?
Because my spot was on 1.44 in BIOS (1.46 real)

Try 1.30VTT, 1.56PLL, 1.55SB. Disable all Spectrums.

What kind of freezes are you getting? Maybe I can help, I used to have a lot of them...