north bridge temp?

hi,
atm i am at 3.5Ghz with my p4 2.8c, this is with 1.62vcore colling with stock hsf.
now when i increase the fsb it becomes unstable even with more vcore, now when i touched my north bridge it was quite hot, i mean if it was just abit hotter it would be painful to touch.
so what i would like to know is, should i put better cooling on the bridge? is this what could be stopping my increase in fsb?
oh any my temps are 36oC sitting and 46oC load(roughly)

1 other question while i am asking, i have ocz gold 3700 2x256mb well i have it running at 2-3-2-6 and that is 266(is that the best, setting?) with 2.85vdimm, i can not get the 3 to go down to 2 nor the 6 to 5?
so what i am thinking about is getting this new mushkin 3500 lvl2 ram 2x256mb, will this help me out at all?
or is the ocz gold i got atm fine?

thanks

i am looking for a nb heatsink but i can not find 1 that will fit the asus p4c800?
does any 1 know which 1's are good?