I assume the multiplier is set to 23x? The problem is, Intel have basically always locked the multipliers on their chips so changing that option will have no effect.
The only way of overclocking Intel chips is by increasing the FSB (Front Side Bus), which on your system should be set to 133Mhz (x4=QDR=533FSB). So if you could increase this you'd be able to get a little extra speed, but I suspect you have no option to modify this?
Even assuming that you can change the FSB, unfortunately you have the fastest northwood 'B' P4 available, which is not going to overclock <i>that</i> far as it's already near the 'ceiling' for that particular core.
So to sum up:
You have a non-overclock-friendly platform;
You appear to be missing the only intel Overclocking option in that BIOS;
You have a chip with little overclocking room anyhow.
If you're not planning to get another CPU to stick in that board, you may be better off selling the CPU & Motherboard and buying a new ABit IS7 and P4 2.6Ghz (800FSB). When coupled with some fast RAM (PC3500 at least) you should be able to overclock that to beyond 3.2Ghz, and achieve better performance than your current rig.
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