i have 3 sticks of supposidly bad ddr ram. a "new" stick of 2700 and one of 2100, and a 3rd of unknown speed which i got out of a huge box of free computer stuff. they all fail the pc check (a self booting diagnostic cd which ive used before when i built computers) ram tester and a few other ram testing progs. specifically the block inversion test is the one which tends to fail. im starting to suspect a bad memory controler on the mobo. the mobo is an ancient msi p4 bored from 2002. its been abused by me for the past several years. im just suspious that all 3 test bad. i dont really have a good stick to test against (and i find buying a new one doesnt mean it will pass).