After an again-and-again search in the forum, I finally realize there is no way to run a mobile P4 on a desktop mobo with the high multiplier except a BIOS mod. Mine is Epox 4PCA3i + Mobile P4 3.06 (533Mhz/512K/D0 w/HT).
1. Isolate GHI# pin with super glue (looks like it works for a P4M CPU only, not a mobile P4)
This is a pretty old thread, and I believe I tried it in last year. I had an impression that it didn't boot at all, even after removing the glue:-(. But fortunately the CPU was back after I short GHI# pin with VSS.
2. Bend VID4 pin (it's for mobile Celeron)
I gave a try too although mine is a P4, but there is no luck for any change, it boots as usual. Multiplier is still locked.
3. RightMark utility (Work for people who has a Prescott core mobile P4)
The P-State Transition in the utility is gray, so there is no luck to set the range for multiplier:-(. So it should work for Prescott only.
AFAIK Dell did sell a Laptop with Mobile P4 on a desktop chipset, something like 845E (CPU can run at full speed). So I believe the only way to enable the CPU runing with high multiplier is a BIOS mod, which is far out of my capability... If someone is volunteer to give a BIOS mod for me, I am happy to provide the BIOS of both my 4PCA3i and the Dell BIOS:-P
Just correct me if I was wrong with anything... Or there is something else I can try?