As the title says, I was watching TV on my PC when it shut down abruptly. I was having problems with the northbridge chipset temperatures so yesterday I installed a waterblock on it too (already had watercooling for CPU and graphics card). When I installed the waterblock I paid extra-attention not to scratch the circuitry on the motherboard and I put insulating washers on the screws that keep the waterblock attached to the motherboard. On my motherboard I have 2 LED's, one in the southbridge area and one between the RAM seats. Tried to power up the PC, fan starts spinning (fan mounted on the watercooling radiator, attached on the motherboard to the CPU fan socket), the southbridge LED comes on normally, but the one between the RAM seats barely shines (should light up as the southbridge one) and the display doesn't come up either. My first thought was on the power supply, so I took a new one I had at the office, installed it and nothing Tried my power supply in a different PC, checks out OK, so that rules out the powers supply. Tried clearing the CMOS, removing everything but one module of RAM (seated in each of the 4 seats), graphics card and one hard-disk, powered up, still nothing. The motherboard speaker stays silent, no beeps at all. Could the problem be the CPU or the motherboard? Would the motherboard speaker beep or display anything on the monitor if the CPU was dead? The manufacturer's site (and forum) isn't helpful at all. Thanks for any input on this issue, it's doing my head in. nitropuppy PS. Machine specs are in my signature.