Will 1G kit run with 2G kit.

I currently have 1G (2X512) Gskill PC4400 kit. Thinking about adding 2GB (2X1G) PC3200 kit to it. I'm sure it'll run but the question is: Will I still be able to run in dual Channel and will I still be able to run in DDR? How does this effect the mem timing?

First of Dual Channel and DDR reffer to same thing as DDR stands for Double Data Rate.

Second, it should technically run in DC with 2T command rate but you might have some complication with Windows cause I heard people having some issues when using more then 2GB or RAM and I thing it's because of the page file.

Since the 2GB kit that you are adding is rated at DDR400 or 200MHz your faster 1GB kit will automatically default at those speeds, but just to be safe I would go into BIOS before you boot into Windows to make sure that timings are set to those used on 2GB kit and that they are compliant to 1GB ones and make sure that Vdimm is not set to high/low for either one of the kits.

Good Luck

First of Dual Channel and DDR reffer to same thing as DDR stands for Double Data Rate.

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I'm pretty sure DDR and dual channel are two completely different things. Example, I can run in DDR (double data rate) on 754 system but not in dual channel because it only have one memory controler. I can also run DDR on a 939 and only run single channel if the RAM are not compatible for dual channel. Dual channel requires same or compatible memory but DDR will allow some minor differences. My assumption is it may or may not run in DDR but will not run in dual channel. That unless I get the same exact RAM (all four stick) but have not tried it.

DDR is the type of memory (Double Data Rate). Dual Channel refers to how they run - dual channel can run at twice the bandwidth as single channel - even though they are the same modules. The dual and single channel depends on your CPU/Motherboard for the most part........but in order to run in dual channel, each stick of memory has to be a "matched pair".

Mdogs444 said:

DDR is the type of memory (Double Data Rate). Dual Channel refers to how they run - dual channel can run at twice the bandwidth as single channel - even though they are the same modules. The dual and single channel depends on your CPU/Motherboard for the most part........but in order to run in dual channel, each stick of memory has to be a "matched pair".

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That's pretty much correct. DDR or double data rate referrs to their data transfer rate. For example, a DDR400 chip sends and receives data twice per clock cycle on a 200MHz memory bus. This results in a data transfer rate of 400MT/s (million transfers per second). On single channel memory running DDR, this would feed the data to the processor via a single channel at a maximum rate of 64 (32bitX2) bits at a time. Resulting in a maximum bandwidth of 3200MBps . Dual-channel memory, on the other hand, utilises two funnels, thereby having the capability to deliver data twice as fast, at up to 128 bits at a time. Resulting in a maximum bandwidth of 6400Mbps.

When you look at Sandra bench, you'll see that the 939 bandwidth is about twice the 754 platform at same FSB speed. Therfor. Dual Channel is different from DDR. You don't necessary have to have a match pair to run DDR. You can have two non-matching PC3200 and can still run in DDR. Dual chanel on the other hand does require matching pair.

I assume that it will probably run in DDR but not in dual channel. Can anyone confirm this?

i'm running 2x512, and 2x1gig together for a total of 3 GB of ram.
It's all running in dual channel, since i have 4 ram slots, the 2x1gig sticks are in dual channel and the 2x512 are also in dual channel. Just check your motherboard manual for the proper way to insert dual channel memory.
In my case the 2x512 has looser timings (2.5-3-3-8) and since the 2x1g can run at those timings as well, i set it to that in the BIOS. I had to run them in 2T and at a memory divider for 166MHz (i never tried at 1:1).
But i've overclocked them back up to 209MHz so the memory divider makes no difference.

Nebuchadnazzar said:

i'm running 2x512, and 2x1gig together for a total of 3 GB of ram.
It's all running in dual channel, since i have 4 ram slots, the 2x1gig sticks are in dual channel and the 2x512 are also in dual channel. Just check your motherboard manual for the proper way to insert dual channel memory.
In my case the 2x512 has looser timings (2.5-3-3-8) and since the 2x1g can run at those timings as well, i set it to that in the BIOS. I had to run them in 2T and at a memory divider for 166MHz (i never tried at 1:1).
But i've overclocked them back up to 209MHz so the memory divider makes no difference.

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Yes... the answer I've been waiting for. Thanks Nebuchadnazzar.

http://www.xtremesystems.org/forums/showthread.php?t=90898&page=5

Post #103

Running my LE's with my 2gn HZ's. Had to run at 2T and that added 1 second to my 1M SuperPi. Works pretty good!