Adding 1GB ram with 1Gb(512x2)already installed

I have 1GB (2x512) of Corsair XMS (Twin1024-3200XL, 2-2-2-5) memory installed in my Motherboard (MSI K8N Neo Platimun.) I want to upgrade my memory to 2GB. After reviewing the Corsair web site I was inable to locate a 1 GB stick with the same memory timings. The closest I found was ( CMX1024-3200C2, 2-3-3-6.) I would like to know if the memory will work with the ram I already have installed. I only have 3 slots on the mother board for the ram. I have been getting mixed reviews from a local retailer about the upgrade. Any help is greatly appreciated. Thanks

It is NEVER recommended to mix modules of different part # / revision #s. There's no 1 GB 2-2-2-5 sticks as there's no ICs that can do that currently.

Along the same line as the previous post, I was wondering if I can use either one of the 1gb of memory with what i have installed now? I have the 2x512mb running & would like to upgrade to 2gb.

 

Installed now: CORSAIR XMS 1GB (2 x 512MB) 184-Pin DDR SDRAM DDR 400 (PC 3200) Unbuffered Dual Channel Kit System Memory Model TWINX1024-3200C2PT - Retail

Item #: N82E16820145450

 

Hoping either will work.

CMX1024-3200

CMX1024-3200C2

 

This will be installed on a Gigabyte mb GIGABYTE GA-K8NSNXP Socket 754 NVIDIA nForce3 250 ATX AMD Motherboard - Retail

Item #: N82E16813128245

 

Thanks in advance for any advice provided.

Ok thanks for the advice