Help chosing memory. 4-4-4-12 vs 5-6-6-15. A good deal? 2gbkit/4gbkit

[crewxp]

Hey, I have a Asus P5w DH Deluxe Motherboard, and I only have 2gb...so I'm looking at a good deal for a memory kit... but the thing Is.. I don't know that much about memory.

I was looking at these two deals...
One was 2x2gb 800MHZ with CL 5-6-6-15 for $159.00
There was also 2 different deals for a 2x1gb Kit with 4-4-4-12 for about $60.00

I don't know much about latency or how it works (the 4-4-4-12 and 5-6-6-15, etc.), so could someone help me out with this? I'ld like to get the 4gb kit, so later on I could get another 4gb, making it 8gb total.....but I don't know if that latency is good.

I'm not overclocking right now, but with my setup, I'm pretty sure I can.

Here's my system specs:
GameXtream 700W PowerSupply
Asus P5w DH Deluxe Mobo
Core2Duo E6600 Processor
Patriot (2x1GB) DDR2 667 (PC2 5300) memory
Custom Water-Cooling Setup

Here's the links to the memory deals.
Patriot Extreme DDR2-800 CL 4-4-4-12
Crucial DDR2 PC2-6400 4-4-4-12

OCZ Vista Upgrade Ed: 2x2GB 800MHz 5-6-6-15


ps: I'm running 667MHZ memory right now, and I don't know if I'm supposed to mix 800 with 667, or if it'd be better off just upgrading it all.

 

[jedimasterben]

When you mix memory of different speeds/latencies, the one with the highest latency/lowest speed will be chosen for maximum compatibility.

So your best bet would be upgrading it all, unless you use very memory intensive programs that would benefit from 6GB total.


CAS latencies are the amounts of cycles the RAM takes to transfer information. Lower latencies = faster performance. It doesn't make <b>too</b> much of a difference, but lower latencies can really help some programs a lot.