DDR2/800: dual channel / latency

[ss_blake]

Couple questions

1. Is there much performance difference between DDR2/800 chips running at 4 x 1GB (dual channel mode) versus 2 x 2GB (dual channel)? Can you run 4 x1GB in dual channel with Asus P5N32-E SLI mobo?

2. How about DDR2/800 2x2GB dual channel low latency (4-4-4-12) versus standard latency (5-5-5-15)?

My CPU is Intel Core2Duo E6600

 

[Mondoman]

Dual channel should work fine either way, but it would be nice to leave a pair of open slots for future expansion, when you move to a 64bit OS and want 6GB of RAM.
Here's some data on the latency issue: http://www.madshrimps.be/?action=getarticle&number=1&artpage=1962&articID=472

 

[samsayit]

I seem to recall having read somewhere that the larger the memory module, the less it performs - i.e. your example 4x1GB vs. 2x2GB the 4x1GB should perform a little better. But I am not sure, just ringing a bell.
Perhaps it could be due to the slower timings on the larger modules....

I think you should answer the question yourself:
Will you, within the lifespan on your current/new system, get the need for more than 4 GB total?
If NO, go with the 4x1GB (usually cheaper anyway, and faster timings).
If YES DEFINATELY, no question about it go with the 2x2GB.

Remember, in 2 years you may be getting new system anyway with DDR3 1366MHz or whatever is in at that time, so don't think too far ahead in time...

 

[samsayit]

And to answer specifically on the timings:
Yes, timings DOES matter. The lower the better. The most important number is the first digit as it is the CAS Latency (also refered to as CL) - i.e. 4-4-4-12. This is the number of clock cycles it takes from when the shipset is asking to access a memory circuit until it actually does access it. And since this is done all the time (read/write in RAM operations), the CAS Latency is important. The other numbers are other latencies but less critical than the CL.