probably bios 11/12 i reckon, i upgraded to an e6600 after that.
ust work it in steps.
im not convinced that you are overclocking properly atm.
ensure you have unlinked the FSB/RAM
up the CPU to 1.40v
DDR2 to 2.1v
NB VTT 1.49v
other one 1.46~
Set the FSB to 1500 (which works out at 375)
should at least boot up, then u can start tetsing cpu and memory.