All asus board have this problem when it detects wrong voltages selected, setting [AUTO] is useless when u r overclocking on this board. I've been having this problem on my P5N-D for quite sometime before i figure it out. In order to pump up the FSB, u need to raise the NB, HT, SB voltage in order to keep the board at the settings u want or the BIOS will reset or fail to POST.

For Example:
I'm using my E8400 @ 3.8ghz now, with 4 ram modules (if u have 2 modules, u can set the NB, HT to lower)

NB: 1.52v
HT: 1.52v
SB: 1.6v

CPU: 1.3125 (with vdrop its 1.264v)
RAM: 2.11v @ 4-4-4-15 timing
FSB: 1688mhz @ 422mhz ram speed (sync mode, 1:1 ratio)


Note: Check your ram voltage first before pumping it high.

No way 1.35v is enough for 4 ram modules on nvidia 750i chipset. The default is 1.32v if set to [AUTO]

as long as theres a fan slapped onto the NB heatsink to keep the temp down. it is ok.

This post has been edited by presto86: Dec 26 2008, 06:10 PM

May i ask, hows the temperature of your cpu like in your BIOS?

are you serious about doing a pencil mod? i have -0.05 vdrop on my P5N-D and i still manage to OC. I don think pencil mod will solve ur issue.