timing

[taintedplay]

hey guys ive never overclocked before, which i plan to change. im not going to oc my q6600 yet, becuase being 15 and jobless, it took me 6 months to save for it and i dont want to void warranty or anything. so i think im getting a old oen from a friend (need to find a 939 chip, i have mobo and the rest). I hear alot about timings for ram, but what exactly does it mean? i know the lower the better, but im still mostly clueless. anyhelp atall would really be great

thanks, tainted

 

[pinoy3000]

Lower timings means you have better overclocking ability.

Say a 4-4-4-12 DDR2 800MHz RAM, that means it runs at 800MHz with a timing of 4-4-4-12. So if you think you are going to run your system with a 400MHz FSB, then this will be a good RAM for you. If you think you are going to run your system with over 400MHz FSB, then its the best RAM for you also. Because you can run this RAM at 1000MHz 5-5-5-15 latency.

So...... now say you have a RAM with 800MHz but latency is 5-5-5-15.

This RAM will perform at 800MHz but if you try to overclock it to say 1000MHz which you need if you are going to run a 500MHz FSB, then you will have to loosen the timings to say.... 6-6-6-18. Unless the RAM will run at 1000MHz at 5-5-5-15. You'll know if you get the BSOD it will not run at that timings but may if you increase the voltage up a bit.

So, as far as CAS Latency goes, its basically how many times the RAM sends signals to your CPU and Mobo.

The lower the better. It's like a ping on an internet connection, the lower the ping, the better.

CAS latency - Wikipedia, the free encyclopedia

It is better to keep your system with a 1:1 FSB:RAM Frequency Ratio.

So if you dont think you are going to overclock your system at all or going to overclock it but will not go over a certain FSB, then get the RAM with the right timing.

With my system right now, I dont run my FSB to over 400MHz but I run my RAM at 1000MHz anyway with a 5-5-5-15 timing.

But if I get a 4GB (2GB x 2) G.Skill RAM with a 5-5-5-15 timing, I will be forced to run it at a 1:1 ratio and a 5-5-5-15 timing over 4-4-4-12. Unless I get the HZ's which will overclock better.

 

[Nagasama]

holy crap dude you should google it...it is a little too complicated (and time consuming) to post all the timings and what they do. there are loads of explanations floating around on the web that make it easier to understand.
hers the basics of the 5 numbers that you will need to know about...
in the example of 4-4-4-12-2T the numbers stand for, respectively:
CAS Latency- RAS to CAS Delay(TRCD)- RAS Precharge(TRP)-TRAS- Command Rate
CAS: number of cycles needed to find the correct address of the data that it is looking for (most important timing).
TRCD (ras to cas): the number of CPU cycles between the CAS and RAS signals used when your RAM is written to, read from, or refreshed.
TRP (Ras precharge): indicates how fast your RAM can terminate the access of one row and start accessing another.
TRAS(active to precharge):the number of CPU cycles between getting a memory bank ready for access and then closing it. this one will affect stablity more than speed, will usually be much higher than others, but you should keep it as low as possible while keeping overclock stable.
Command Rate: higher (2T) setting slower overall speed but will allow you way more of an overclock on your memory. 1T will be faster, but you wont get over stock speed with ddr2. actually, if you are using s939, you will use ddr and it should be able to run 1T.
hope this helps.

EDIT: crikey i cant believe i typed all that out lol.
i agree with what pinoy says except that if you are goin gto run an AMD s939, the 1:1 ram/htt ratio makes no difference at all. even with the c2ds i dont think it is that important anymore.