Is CAS latency overrated?

I'm going to upgrade my Dell D420 to 2 GB ram.

Should I go with the lowest CAS latency but trade off some speed?

Here are my choices...


http://www.newegg.com/Product/Product.aspx?Item=N82E16820231153

http://www.newegg.com/Product/Product.aspx?Item=N82E16820104100

 

Yes cas is overrated. Get the faster ram.
You could even change the timings with thaiphoon burner (lower any timings you want).

But why don't you buy an 800mhz stick (it can run at 667 and 533).

 

Back in the day, it use to matter. Nowadays, all chipsets support dividers..

 

If you get out your calculator, you will discover that CL=4 at 667MHz is the same elapsed time as CL=3 at 533MHz (and CL=5 at 800MHz). Most likely the 667MHz RAM will also support CL3 at 533MHz.

The higher the frequency then the shorter the clock pulses so the RAM needs to wait for more pulses before the memory is ready to read. Once that time arrives, then the data will move a bit faster if the frequency is higher.

John

 

Most likely you can run the 667mhz ram @ 667mhz and lower the CAS to 3 with thaiphoon burner.

Worked for my 667mhz ram. In fact I even overclocked it to 830mhz CAS 5.

 

In desktops, memory speed can be useful for overclocking (as overclocking can make a significant difference), but in notebooks, there isn't much point in worrying about memory timings and the like.

 

The bottleneck is your processor, FSB and various microcontrollers on your computer. RAM clock frequency and bus speed is way greater than what a C2D can utilize. So worry about CAS latency is pointless.