DDR2 800 or DDR2 1066

Aneesh@4GHz

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Sep 20, 2009
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I have a ASUS P5KPL AM/PS,
asus says it supports ddr2 1066,Does it mean that my mobo can carry ddr2 1066 sticks?

OR

800MHz DDR2 can be oc to 1066?
What will happen if i put ddr2 1066 sticks in my mobo?

Thanks in advance!
 
First of all, there ain't no such thing as DDR2-1066 RAM. Got your attention now, yes? :) DDR2-1066 RAM is simply DDR2-800 RAM that has been tested to run at the higher speed, usually at an increased voltage and more relaxed timings.

Any good DDR2-800 RAM will run at 1066 speeds under those conditions.
 

Beetlebox

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Apr 19, 2009
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While this is mostly true (1066 being predominately PC2-6400 OC'd) there do exist PC2-8500 chips such as MT47H128M8CF-187E, just don't expect to find them on your everyday local DIMMs.

What about CT2KIT12864AA1067 ? true PC2-8500 or not, I can not see what chips are used to say one way or the other.
 


Yes it is true 8500, just make sure whatever you buy is on the QVL list....
 
I would suggest you get a set of 2x 2Gb since your board only has 2 slots. If you decide to use 2x 1Gb modules you will endup paying more in the future since you will end up buying/upgrading the 2Gb anyways. And the fact that you will have 2 extra sticks laying around....personal experience =)

Here is the QVL :

http://i683.photobucket.com/albums/vv199/OvrClkr/newerqvl.jpg

newerqvl.jpg


 
It's been a couple of years since I have visited the JEDEC (JEDEC Solid State Technology Association, formerly known as the Joint Electron Devices Engineering Council) website. The last time I looked, they said they weren't going to do a 1066 standard. Should have went back sooner. :(

There is a recently published JEDEC standard for DDR2-1066 specialty (their words) RAM. After wading through nearly 100 pages of a pretty technical document, I believe that the simplest way to tell if a particular RAM is JEDEC compliant is to check the vcc. If the vcc is 1.8 volts +/- 0.1 volts at 1066 frequencies, it may be real 1066 RAM.

I checked the specs on the MT47H128M8CF-187E RAM. It runs at CL7 latency. Considering that CL4 DDR2-800 RAM is commonly available, and most of it will run at CL5 at 1066 speeds, I am not sure that the CL7 latency is really worth it.

But you are right. True DDR2-1066 RAM does exist.