memory speed loss dual core

[pcuser#1]

Hello. I just recently upgraded CPU on my system from Athlon 64 3500+
(Winchester) to 4200+ (Manchester). My memory bandwidth went from 74%
efficiency to 64%. I use Corsair Value (2.5-3-3-8) dual channel. Why the mem
bandwidth is slower on dual than on single core? Thanks for any info.

 

[andrew.gullans]

Benchmarks and numbers mean very little compared to real-world
*percievable* differences. Did you notice a general improvement or not
from your upgrade? Keep in mind that you have TWO cores using ONE
motherboard's RAM, which means they might have to be polite and ask
each other stuff like: "Terribly sorry, old chap, but would it be a
bother if I took a peak at 00E00R58FF2?" "No trouble at all, governor,
go right ahead! Oh, and while we're at it, might I parse off the last
512 megabytes for a large pagefile I'm compiling?" Yeah, it's the
damndest thing; for some reason, those Manchester dual cores talk to
each other in Proper Queen's British.