I've got a GA-7VA (KT 400 chipset) mobo. Used to have a Pally 2000 and generic PC2100 RAM. Recently bought a T'bred 2600 (166 FSB), and a stick of Corsair XMS2700 Platinum CAS 2 512Mb. After installing both, system was very unstable. Ran memtest on it, and it failed. Messing around with memory timings and voltage didn't help. Returned to overclockers.co.uk, and they say they ran memtest on it with no problems and have returned it to me. I then tested the old generic RAM, one stick of 256 Mb failed, one passed. However system is stable at 133 FSB with both sticks of the old RAM.
Any ideas gratefully received!

Cheers

the only thing i no off the causes perfectly working ram to fail memtest is overclocking. Is ur FSB set correctly? Is ur ram set to NO higher than 100%FSB (166mhz) 6-2-2-T2? anymore and memtest starts producing errors. also make sure the voltage is right or u will fry it (2.5v)
hope that helps

Steg

Did you try the latest motherboard BIOS? It may possibly be incompatability between the Corsair RAM and your mobo.