I would say that you Modify your Multiplier and Memory ratio! 273 FSB sure the hell isn't high enough to support 450 Mhz of Data per channel!
Dunno what your board is, but 400 x 8 = 3.2 for processor speed which should be simple for the chip. That way your Memory is running at a true 800 at least! It looks all nice and pretty to have it opporating faster, but does little.
Wanna do a simple test? Go to stock, set the mem to where you have it now, and test with something or other, Then simply up the FSB from 266 to 400 or anything higher and look at your Mems Latency and junk.
Gets much faster for simply raising the FSB! Wonder why? If the FSB is the pathways your memory has to take to communicate with other stuff, how can you pack 450+ Mhz worth of data on a bus thats 280?
You may have to set the MCP voltage to 1.5, or 1.55. Thats the NB, I think. You may also have to set your VCore a bit high, because those boards have a large VDrop and droop. Try 1.47500 in the Bios for now, just to get her to boot!
on break right now , yea in benchmarks e67xx beats e7200 all the way (dunno if its oc'ed or no tho), hmm no new games yet & why ea makes all westwood's (C&C) games cartoon, while original C&C was serious, explosive with twist of dark humors (new school) , new C&C (ea's) are light + colorfuly cartoon (pre-school ).
also the old (westwood) had great FMV of fighting units (tank etc.) less video, the newer (C&C3) had interview like of bunch peps talking / giving you orders, lol