I bought a lot of RAM, 20 sticks, for some desktops that I'm rebuilding. Rebuilding as on upgrading, as most or all work. I put in 2 1Gb sticks (Samsung k4h510438b-TCB3) into some d51s desktops. The max should be 2 1gb's at or around 333mhz but the computer would not boot. It turns on and the lights all flash like normal but will not even show the boot screen. So I put in the old RAM after fildleing around with the 1gb sticks like changes out which dimm sockets and it booted up. These were just 2 256mb sticks (hyb25d256800bt-6). They both should be the same speed too, that's what I don't understand. If I messed upped somewhere please tell me where. Thanks!