Ram CAS and Timing; and digital vs analog‏

I emailed you this question yesterday cause I was watching the inbox vids in order and didn't get to the one where you said to post it on here yet... but I did today, so here are my questions

Can you explain what ram CAS and timing does, what it affects, how it work... I'm not even sure how to ask the question cause all I know about ram is capacity and speed.

What exactly is the difference between digital and analog?  Isn't it electrical signals going through both cables?  I hear "don't use VGA cause its analog, DVI (or whatever else) is better cause its digital!" all the time.  Other than resolution I don't see any difference.  If I'm running a 1080p monitor at 60Hz, is there any advantage to using digital over analog?

I can try to rough cut it until someone else chimes in.

Basically CAS latency has to do with how the RAM handles memory in a timing sense. Generally speaking, in the past, the lower the numbers the better because of things like Bus speeds, etc, but from what I've read/watched, since prepping for my build last year, those numbers aren't as important anymore as the frequency of the RAM is because the bottlenecks involved are virtually inperceptible.

The main thing to know about Digital vs Analog with respect to your connections is that the digital will understandibly look prettier, probably more responsive, and a number of other things that my cramping hands don't want to type right now. Basically, you're not getting what you pay for if you're using a VGA connection on a good display/GPU setup. Well, unless it's a server monitor that's only used for monitoring, then you're not wasting money. I don't 'think' that VGA can handle the higher frame rates either.

well, i did a write up on ram timings a long time ago, i would google for it but im tired. i will later.


as for digital and analog... its all how its decoded.

digital is a 1 or 0, so if the voltage is above a threshold it will be read as a 1. digital means the data is encoded in 1's and 0's send, then decoded. it is very hard to corrupt a digital signal (compared to analog).

analog is a value between 0 and 1023. its based on voltage.... the change in this voltage means a change in value because such a small change in voltage will change the value, its a lot easier for analog signals to become a bit messed up (attinuation, magnetic interferance, impedance mismach, so on). in all actuallity, you would need a very long analog cable for these to play a major factor. and the cable is usually shielded by a grounded wire mesh. so... to you, there is no difference.


analog: gimmicy things like gold plating have a valid clame, but its pointless.

digital: gold plating doesnt mean shit.

thanks for the replies

ztrain, I tried googling for your ram write up but couldnt find anything.. anything else I found about ram timing and CAS I couldn't understand...

Basically, go for the RAM with the best reviews and the capacity you want. If you have two that are essentially the same, but one is cheaper, go cheaper as the numbers aren't as important.

but I still wanna know what it is and what it does...  Specifically the 9-9-9-24 numbers (or a something like that). 

Cas Latency is basically how long it takes until the RAM actuallystarts doing anything with the data. Lower CL is great, especially for editing. I'm a fan of 1600mHz CL6 kits, but those are (sadly) not made any longer, and must be scored on eBay. As long as you have a about a 178 to 1 ratio of frequency to CL, you're good. Any lower, and the CL is too high. Any higher of a ratio, the better for you.


heres the post. looking back at it, i think i might have messed up converting the clock cycles to seconds.... might have done khz instead of mhz. but it will give you the general idea... always a good idea to check the math in posts yourself anyway.


hope it gives a bit of insight about how ram works.

read your post, so the 9-9-9-27 is the columns and rows thing?



CAS latancy (column access strobe) is your first number, and the most important

Row access strobe to CAS delay.

Row precharge time

Row active time.