i know that a pentium 4 has a quad pumped bus speed. my ddr memory has a rating of 400mhz, but my bios only says it has 200mhz. what is up with this, why isn't this hardware just rated at 200mhz for the ram and the non quad pumped speed?

p4 at 3330mhz
256mb pc3200
80gb wd hdd
geforce 4 mx440 teporary
Audigy 2 ZS
dvd and cd burner
only 15 so i am tight on cash

Well the BIOS says 200MHZ because that is the real speed of the Ram. The effective speed of the RAM is 400MHZ since DDR stands for Double Data Rate, or two instructions per clock cycle.

Since Intel quad pumps their bus speeds, the 200MHZ DDR 400 runs at an effective speed of 800MHZ, or 4 instructions per clock cycle.

Sempron 2400+ OCed to 2.2GHZ
Abit NF7-S2
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fsb = front side bus (frequency your computer runs at)

cpu = fsb*multiplier (multiplier is locked, and varies by cpu)
ram = fsb (at 1:1 ratio...if you use a multiplier, it will be a fraction of your fsb)

effective speeds:
effective fsb = fsb*4 (pentiums are quad-pumped)
effective ram = fsb*2 (if in dual channel mode)

So, at stock speeds (fsb=200), my computer with a cpu (multiplier=15...I have a 3.0 ghz cpu):

fsb = 200
cpu = 15*200 = 3000 mhz = 3.0 ghz
ram = 200 mhz

effective fsb = 200*4 = 800 mhz
ram = 200*2 = 400 mhz (in dual channel mode)

BIOS reports the true figures, not the effective speeds (which are for marketing purposes, so you can see how much faster it'd be compared to older chips). It wouldn't be right to say the fsb is actually going at 800 mhz...it just means it's doing as much work it would have been doing if it were actually at 800 mhz