Memory Timing Questions

andytg7

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Apr 25, 2007
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Hello everyone. I have a couple questions in regards to the Memory Timings I set manually. First off, my mother board is an ASUS P5W DH Deluxe. I have 2GB Memory (2x1024 in Dual Channel).

This is the Memory I'm using: http://www.corsair.com/_datasheets/TWIN2X2048-6400C4PRO.pdf
As you can see the timings are: 4-4-4-12-2T at 2.1V.

My motherboard allows me to set the following options:
DRAM CAS# Latency - which I set to 4.
DRAM RAS# Precharge - which I set to 4.
DRAM RAS# to CAS# Delay - which I set to 4.
DRAM RAS# Activate to Precharge Delay - which I set to 12.
Now comes my first question...in addition to the above options, it asks me for a DRAM Write Recovery Time - which can be anything from 2-6 Clocks. What value is the correct one for my memory?

My second question has to do with the 2T value. If I can't find a location in my BIOS to set this, am I to assume my BIOS automatically detects and sets this value? Or where may I find the option to set this?
 

hughyhunter

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I have never seen this option before called DRAM write recovery time. I would however with those timings probably set it to 4 or maybe even 5.

There are some mobo's (ones that i've seen have been intel based chipsets) that cant run anything (no other option) but 2T command rates. So if you want it to be 2T than you are fine. If you want 1T though you wont get it with that mobo more than likely.

 

andytg7

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Thanks hughyhunter.

Anyone else have any info explaining what the DRAM Write Recovery Time is and what I should set it to?
 

leon2006

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Write Time Recovery:

2 to 3 should work. fewer clock is better as long as your memory can keep up with it.

2T
DRAM Command Rate: set it consistent with your DRAM datasheet 2T



 

andytg7

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hughyhunter - Set to 11? Defaults to 23-24? It can't go nearly that high! The only possible values are anything from 2-6 clocks. You lost me. :(

leon2006 - Is there anyway to tell whether or not your memory can keep up with it, other than of course setting it and seeing what happens?
I'll look for a DRAM Command Rate option. If I find it I'll set it to 2T, but I don't believe I saw such a option the last time I was in the BIOS...
 

leon2006

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You can run games and that will certainly freeze the computer.

I have a script that use up whatever memory (flip the bytes). If my settings are in-correct my computer stops or freeze.

In most cases the computer don't boot at all....Thats what happens when i mess up my settings.
 

hughyhunter

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I'm sorry... I was thinking of TRFC which should be around 32, TWTR should be around 8, TRC should be around 26 (this is the one I run at 11).

Oops... I have no idea where write recovery time is in my bios!