Please Explain

[Indobos]

I am trying to better understand all the numbers here. So be gentle. What do the numbers represent in Ram Timmings. Ex. 4-4-4-12 1t or 5-5-5-15 2t. What do the individual numbers represent and what does the 1t or 2t mean. If b!gapl sees this, he might bonk me since I may have asked him this before. But if you could explain. I will favorite this post so i can refer till my eyes pop out and it sticks in my head. Thanks all.

 

[b1gapl]

lol...I won't bonk you for that. Or whatever that means. At the time you asked, I didn't really understand. But now that I know....I just explained it recently this morning, to another member. Here is the thread:
http://www.techist.com/forums/f10/ram-timings-153751/

Think of the RAM as a spreadsheet, with rows and columns. And think of the timings, as the time it takes to access those rows and columns.

CAS - Column Address Select
RAS - Row Address Select

Each number represents a different function:

4.....CL - CAS Latency
4.....tRCD - The time between RAS and CAS signals
4.....tRP - The time between switching a row
12...tRAS - The time between activating and deactivating a row.


CL or Cas Latency is probably the most important part for RAM timings. It is time between it's signal and the data available for processing. So the lower the CAS, the faster it can get and receive data.

tRCD is the time between, a row being selected/activated, and the column in the row being activated, by the CAS signal. In other words, the time between RAS to CAS being accessed.

tRP is the time between accessing different rows. A row has to be activated, in order to access the information. And before the RAM can access another row, the row that was just accessed, has to be deactivated. So in order words, the time between accessing one row to another.

tRAS is the time between the memory getting the signal, to access a row.

I tried my best to explain it, so please correct me if I'm wrong.

 

[Indobos]

Wow. Nice that clears that up. 1 other thing. What does the 1t or 2t stand for? BONK is basically what you do to someone that asks something repeatedly. The phrase refers to someone hitting another on his head with an object on the head in an attempt to ingrain the information into the head. . Not sure if you can find that somewhere, but that was my interpetation of the term.

 

[b1gapl]

lol...I see.

Well the 1T or 2T is the Command Rate. And this is the delay or time between the RAM getting the signal to select another chip, to the time the command can be issued.