266 on a p4 northwood

just got corsair ddr400 1gb (dual channel 2x512)

i put it in my dfi lanparty with my p4 northwood (400fsb) and it wont let me run the ram any higher than 266mhz (unless i overclock)

i read in the instruction manual that i can only run 266 (at default) with a 400FSB, why is this? should i just overclock so it runs at 400mhz?

also i have the ram in slots dimm 1 and dimm 2 and it says im running in single channel mode, which slots do i need the ram in to run in dual channel or do i need a 800fsb processor?



thanks

For dual channel you need slots 1 and 3 or 2 and 4 i believe, check the manual! There may not be an option to run a 4:5 divider on that board... again read the manual.

If I'm reading your sig correctly your P4 is an "A" Northwood, in which case your cpu is actually running 400/4 = 100MHz FSB. At 1:1, your mobo can only set the ram to DDR200. But seeing as you are at DDR266 setting in the mobo, the ram is already being overclocked in relation to the cpu fsb. In order to run DDR400, your mobo needs a setting of 1:2 cpu:ram ratio. I don't think you are going to be able to get that.

ok i found that dim1&2 work on 1st channel and 3&4 are the 2nd channel so im now running in dual. ive turned my fsb up to 114x4 so im now running at 2.29ghz and my ram at 303mhz... i can go higher but dunno if i should what do you lot think?

You can probably keep upping the fsb until you reach the limit of the cpu. Your ram should be able to handle it no problem. Just keep an eye on your cpu temperature and check for stability after each increase.