CAS latency vs. speed

Hi. Is it better to get a 400 MHz memory with CAS latency 3, or 533 MHz memory with CAS latency 4 (if your computer supports both these things)? Thanks,

Bill

 

I think CAS 4 at 533 Mhz easily beats CAS 3 400Mhz or even CAS 2.5 @ 400. Atleast that has been my experience I had with my desktop as well as laptop( I used Kingston regular, Kinston Hyper Memory, Corasir Value RAM, GEIL etc with different systems, laptops).

That is the case with my current laptop as with CAS 3@DDR400 is faster than CAS2.5@DDR333.

 

You'll get more bandwidth out of the 533MHz memory. Either way, there isn't that big of a difference between the two, but faster is better, so go for 533.

 

Tsk, tsk, tsk. ChazMan you are usually correct, but not this time

I don't remember the specifics, but bandwidth vs latency was extensively tested over at Anandtech and Tomshardware I believe.

In some cases bandwidth was the way to go and beat out the modules running lower speeds with lower latencies, but it all depends on what type of ram you are running. DDR1 vs DDR2.

400mhz low latency ram beat out some high bandwidth modules.

So go do some reading, but to make things simple, with DDR2 ram anything up to 533mhz bandwidth is the deciding factor and not latency. Anything above that speed is where latencies come into play.

Cheers,
Mike

 

Hey Mike - we're talking about DDR2-400 and DDR2-533.

 

Very well said, Mike.

 

Don't forget - it's DDR2-400 vs DDR2-533. Not DDR400 vs DDR2-533.

 

Should I just reiterate what was being said for the third time? LOL