MA790GP-UD4H and boot issues

I am not sure if this is right section, but here goes.

I have a X3 720BE on a MA790GP-UD4H with 4gb Gskill RAM. I am running 32 bit XP and the system is overclocked at 3.0gh and the 4th core is unlocked. The system runs very stable and I have noticed no problems While running. p

That being said, when I do a dry boot XP will not boot up (sometimes). When this happens, sometimes if I hit the re-set button it will start up. Sometimes, if I unplug my USB drive it will boot up. This morning I had to clear the BIOS via jumper and it booted up. I un-did the OC and 4th core, bringing the system back to stock, and the problem still is there. I also notice that sometimes when this occurs, there is a redundant clicking coming from my DVD burner, like it is trying to boot from the CD, but BIOS shows the SATA drive as the first boot option. I am stumped.

It doesn't do this when I re-start windows wihtout turning off the power, only when I shut the machine completely off. And even then it's not every time.

any ideas?