Question about CAS ratings vs amount of ram

[rile0161]

I currently have 256 megs of Corsair CAS 2.0 PC2700 in my system. I am going to add another stick of RAM, but I'm kind of torn as to which I should get. I can get another stick of 256 CAS 2.0 , or for an extra $30 get a 512 meg stick of Samsung CAS 2.5 PC2700. My big question is how much of an effect does the CAS rating have on performance? Would I be better off with 512 of CAS 2.0 or with 768 megs of CAS 2.5? Any opinions would be greatly appreciated, or even links to articles talking about this thing. I tried googling for it, but the only results I could find were rather vague about the subject. Thanks!

 

[Jeff7]

I'd think that 512 of CAS 2 would be better; I doubt you'll ever really use the full 512MB anyway, so you might as well go for speed over more MB. I have 512MB, with 40MB of it used as a RAMdrive, and I don't think I've yet really run out of RAM.

 

[Kingofcomputer]

Crucial says CAS "is the length of time between memory receiving a command to read data, and the first piece of data being output from memory.
Latency only affects the initial burst of data. Once data starts flowing, there is no effect. Bear in mind, a clock cycle for a PC100 module is 10 nanoseconds so you probably won't notice a significant performance difference."

 

[Woodchuck2000]

I'd always go for quantity over speed (within reason.)
I'd much rather have 512Mb of PC133 than 256Mb of PC2700. If anything you do might benefit from more than 512Mb (which is quite likely over the next year or so) then go for 768Mb. You'll only notice the difference if you're a benchmark lover.