ASUS A8V (Socket939) AGP/PCI lock?

I just built my new rig based on ASUS A8V mobo and Athlon64 3500+ CPU. So
far the system works great when "FSB" is overclocked to 217MHz FSB. No need
to change multiplier or increase the CPU core voltage.

I saw in the amdzone review of this board that there should be a line in
BIOS to lock the AGP/PCI speed? I could not find that. I updated the bios to
the latest version (dated 6/18/04... I think?), but still no AGP/PCI lock...

I suspect the AGP/PCI lock does not work, because I got my HD corrupted when
overclocked the "FSB" to 224MHz. This was with the original bios. (I did not
try to exceed that with the new BIOS... because I'm tired of making a new
windows install again...) If the lock is working... this should not happen?
It looks just like the earlier two Athlon64 computers I built to my friends.
They too were based on VIA chipset... and they too corrupted the disk if I
exceeded the approx. 220MHz.

Suggestions, comments?

KMS