P4 2.6ghz OC'ed to 3.72ghz....can I get any faster with what i have?

I have OC'ed my P4 2.6ghz /w 512k cache to 3.72ghz. It took me about 5 to 6 hours of tweaking with voltage and the fsb. I've never OC'ed a a computer til now. I bought the Thermalake Aquarius II and the temp is very consistant at 90 feren. or 30 celc. .. Well my real question is..... is there anyone out there who has OC'ed any higher or have and good tips or tricks it getting it higher... I'm even running some crappy RAM that is (1) 512meg pc2700 infineon. I have read that ram makes a huge difference in stability. If i replaced it, what should i replace it with? I should be able to hit the 4.0+ghz?

My MoBo is a Ai7 abit, Geforce4 Ti 4200.

some input would be greatly appreciated....

really this surprise to me, but i cant find the post that a member of techspot successfully oc'ed the 3.2ghz p4 prescott lga775 to 6667mhz by using dry ice experiment, TECHSPOT IF YOU ALL READ THIS, HELP ME FIND THE POST WHICH A MEMBER SUCCESSFUL OVERCLOCKED P4 PRESCOTT to 6.7ghz PLS!

OOps my mistake, I found the post that exactly running at P4 6009MHZ! Check it out. The team is using Prescott 540. My mistake, sorry :unch:

http://www.techspot.com/story15725.html

Have a nice day,

Lucan, a.k.a The Reckoning :cool: