On Wed, 07 Jan 2009 12:27:27 -0500, Paul wrote:

No, the computer adjusts the clock rate, according to bus loading. Three
sticks of memory is a heavy load for the bus, which is why it is using
slow settings.

By installing only two sticks, a higher clock speed can be used. So your
2x1GB is a better way to run the computer, than 2x1GB+512MB. 2x1GB would
be the best compromise between memory capacity and operating speed.

For my motherboard, I read that the DDR will drop to 333 if I use the
maximum 4gigs, which would be 1gig per each of the 4 slots. I am now
using 2x1GBs and 2x512MBs, which is using every slot, but I am still
running at 400.