It's a supported speed but keep in mind your playing with old stuff.
Sometimes old stuff gets fussy.
These folks guarantee their stuff will work.
http://www.crucial.com/store/mpartspecs.aspx?mtbpoid=466CD90EA5CA7304
Hi, was just wondering if this "Corsair TWIN2x2048-6400C5C 4GB 800MHz C5 DDR2" would be compatible with the Foxconn G31MX Motherboard.
I know it takes DDR2 but was just making certain it will be compatible before I purchase it.

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