cisco this is a real tough one. #1 make sure the ram is not covered by a heat spreader. true sammy 3200 does not need one. the last 4 charachters on the chip are tcc4. that designates ddr 400. finally make sure it is a repuitable pcb. preferably one with samsung printed on it. I have a stick of what I thought to be true sammy 3200. no heatspreader visible correct part #s but poor quality pcb. the ram is junk. will not do anything but the most relaxed timings. I'm talking cas3 5-5-9. its terrible i have to set that just to run at 205 fsb. luckily the vendor I bought it from guarenteed it to run at 200 cas2.5 next time I can get to a show I'm gonna get a refund and buy some corsair.