Asus Motherboard

[herm]

Need some computer help here.

I am going to purchase a motherboard and memory. I have
a Core 2 Duo 6400 processor, and was looking at the
Asus P5W DH deluxe motherboard.

I do NOT want to overclock.

For memory, I normally buy a speed that matches the
processor and motherboard so they operate 1 to 1. My current
setup has a CPU bus speed of 800, pc3200 DDR memory, and
an ASUS p4p800 that will handle that front side bus.

Here is the question:

For my new setup the CPU bus speed is 1066. The front side bus
of the motherboad says 1066/800. Good so far. But the spec that
ASUS gives for memory is:

Dual channel memory architecture
4 x 240-pin DIMM sockets support max.
8GB DDR2 800/ 667/ 533 ECC and non-ECC memory

So should I buy 1066 memory? (PC2-8500)

herm

[motherone]

I think the current "standard" is DDR2-667. Anything above that is for "overclocking," whether you OC the CPU or the memory bus.

Too bad you don't want to OC.. The Core 2 Duo's are great for that

[herm]

Hmmm. I thought you should match your memory speed to the
CPU bus speed for best possible data access (one for one, no wait
states).

With 667 memory and 1066 CPU, aren't you creating a mismatch?
As in, the CPU is waiting on the memory?

herm

[motherone]

Not really. Memory can rarely can keep up with CPU FSB speeds. You can look back to older systems, and almost all of them have more CPU bus bandwidth than memory bandwidth.

Plus, don't forget that on an intel-based system, everything still has to go through the northbridge. Athlons migrated to on-board memory controllers starting with the original Socket 754 Athlon64's, so on their I/O requests to the system go through the "northbridge."

On Intel systems, I/O requests will also need to be shared with the memory access requests. Intel does enough tricks (mainly with cache sizes) on the CPU to get around the fact that they have off-board memory controllers, so don't worry about it. Just verify in the manual what speed memory they recommend. Anything higher than the "standard" will only aid you if you overclock, or possibly to lower the bank timing.

I personally can't wait for the cheaper quad core intels and the 65nm AMD die shrinks to come out.

[herm]

Thanks for the info, Mother.

I found an article on Toms Hardware that agrees with you:

On the Intel side, DDR2-533 in dual-channel mode is an exact match in both bandwidth and clock speed to its current FSB1066, and DDR2-667 in dual-channel mode exactly matches the next-generation FSB1333. Slightly better performance numbers are often achieved using faster-than-matching memory, but this is mostly due to decreased latency as cycle times become shorter.

Toms Hardware Article

So 533 it is! Saved me some bucks, for sure....

[motherone]

No problem. Glad I could help!