I used to have the exact same combo. It would turn on at 4GHz but wasn't stable even overvolted and using an XP-120 with Panaflo. The thing with that motherboard (unless fixed in BIOS update) is that it has a FSB "hole" from 199Mhz down to somewhere in the 160's or so, where the board just won't POST, so my Deleron 330 will POST at 4GHz unstable, but wouldn't POST below that until the low 3GHz range.