and an older Hitachi SATA HDD that I had already. It worked excellently for awhile. Last week, i ordered a Western Digital 1TB drive as an upgrade. After swapping out the drives (I planned to copy the data with a USB Enclosure) I booted the machine, and got nothing on the monitor (it didn't power on.) Fairly perplexed, I put the old hard drive back in and tried again. Still nothing. I dismantled everything and tried with only the motherboard, ram, cpu, and graphics card. still nothing. I removed the motherboard and inspected the case for shorts, although it had been working fine for weeks, and I hadn't even touched any of the components except for the hard drive mounts and SATA connectors. I tried it with a borrowed PFG 9800GT card, with the same results. Does someone have any ideas as to the cause of this? Thanks in advance for your answers.