My result with P5E & P5K-Pro
P5E (0605) vCore 1,525 (BIOS set) vNB 1,61 - Q9300 max stable at 433x7,5
P5K-Pro (0904) vCore 1,525 (BIOS set) vNB 1,41 - Q9300 max stable at 480x7,5
I 'll try P5K-Deluxe later