Stuck at 3.15 ghz

[Zxcs]

I am trying to OC my northwood p4 2.8ghz and keep getting stuck at 150mhz fsb. I am using a stock HSF and pc2700 ram @ 1:1 FSBRAM (2.5-3-3-6).
Also, was wondering whether 1.6v vcore is maybe a lil too high for stock cooling?
Any ideas what I could do?

Thanks

 

[Seongmin]

Hmmm, your motherboard may be holding you back, depending on which one you have, or maybe you should try to loosen the timings on your ram. I had the same problem as you until I changed the dividers to 1:1 and now, I'm at 3.42 stable at 1.60 v using the stock cooling xP. Good luck!

 

[Zxcs]

Changed the RAM timings to 2.5-4-4-8 and still can't go any higher, checked the mobo and it supports up to 500mhz fsb. I'm gunna try with a ram ratio to see if that helps