| I can't find any documentation in regards to that MB, but many don't like 3 out of 4 slots filled.
the faster RAM should slow itself down, either that or will have to be done manually via the BIOS.
Pull the 256 and leave the 2 larger in there and see what happens.
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Silverstone ST405, AMD64 3500+ Winchester, Gigabyte GA-K8NXP-SLi,
4x512MB Generic, Palit 8600GT Super, 120GB WD SATA, 2x 320GB Seagate, Asus LightScribe DVDRW |