Success! I have updated the BIOS to v. 5.31 and upgraded the CPU to the Q9400. The only issue I ran into was the CPU kit not containing the correct heatsink and fan for my MB (I least I think it was incorrect). My setup uses 4 screw-in mounts and the one supplied has plastic push and lock-in connectors. I added some thermal gel to my existing fan and reused it. The CPU core(s) temperature is running at a steady 37C and seems to be OK. I may invest in a better cooling system soon just to be safe. I'll be sure to post if anything unusual happens.
I also installed a Q9400. Where did you get the BIOS update?