DDR RAM CAS Latency Question

[IQJUMPuw]

Hello everyone

I've been wondering what

PC2700 CAS 2 (2-2-2-5-1T)

PC3200 CAS 2 (2-3-2-6-1T)

meant. I know that 1T stands for 1T command and is faster than 2T command. But what about those 4 numbers? I have Gigabyte GA-7VRXP and when I go to RAM settings in BIOS, I can change the RAM settings to: Normal, Fast, and Ultra Performance. Frequency to: Auto, 266MHz, 333MHz, and 400MHz... CAS to: 2, and 2.5

I've been running my Samsung CTL PC2700 RAM @ 166MHz, Ultra Performance, CAS 2. Would that be equal to (2-2-2-5-1T)? Because I just got a Kingston HyperX PC2700 CAS 2 (2-2-2-5-1T), but it wouldn't boot up with Fast or Ultra performance enabled... It will boot up at Normal Performance CAS2, but not with Fast or Ultra Performance enabled... Can someone please help?

Thanks so much!

 

[IQJUMPuw]

Ok what the heck is CAS Latency 2-3-3-6-T1?? Urgh... Can someone please tell me what they stand for?

 

[nick1985]

the first number is basically all that matters. if its 2, your good to go.

 

[LesPaul]

actually, the other numbers make a pretty significant difference too. Here's a good article on what it all means, and on the last page is a guide for how to tweak your memory timings for best performance.

http://www17.tomshardware.com/howto/20030701/index.html

 

[IQJUMPuw]

So the first number stands for CAS latency? So if it's 2, it means it's running at CAS2, right?

But how come my HyperX runs @ CAS2, but wouldn't run with Ultra Performance enabled?