In article , "KILOWATT"
wrote:

Hi everyones...thanks to read.

Two basic questions i could not get an answer after 1 hour of checking old
posts:

1- Since most Pentiums 4 CPUs sold are with a 800MHZ FSB, it is correct to
assume that the ram will always be a bottleneck unless i use the newer
800MHz DDR module?

2- If i use two 667MHz matched pair modules in dual channel, will the ram
fsb will still be a bottleneck compared to the 800MHz cpu fsb?

TIA for your reply.


--
Alain(alias:Kilowatt)
Montréal Québec
PS: 1000 excuses for grammatical errors or
omissions, i'm a "pure" french canadian! :-)
(If replying also by e-mail, remove
"no spam" from the adress.)

Don't forget that dual channel is 128 bits wide, and the
CPU bus is 64 bits wide. On a DDR based system, a FSB800
processor was perfectly balanced with two DDR400 DIMMs in
dual channel mode. (I.e. 6400MB/sec FSB is equal to two
3200MB/sec DIMMs).

If you look at the results here with a Netburst processor,
there is hardly any incentive to spend as much on memory
as you spent on the processor. Anything at or over DDR2-533
is enough.

If you used DDR2-800, the memory subsystem to FSB800 bandwidth
ratio would be 2:1, meaning the burst of read data is being
buffered in the Northbridge.

http://www.anandtech.com/memory/showdoc.aspx?i=2732&p=4

Paul