I'm built my own desktop computer this past june running windows 7&8 with no problems until one morning my hard disk became undetectable. I am using an ASUS P8P67-M PRO Motherboard. I have my hard drive connected a WD 5400RPM 500GB connected to a SATA 6.0Gb/s port located away from all the other SATA ports(This is where i connected it when i first built my computer.), but now my HDD does not show up in my BIOS at all. I've done some research and followed instructions to change the mode to IDE/AHCI mode, but no luck, my drive remains undetectable. When i try to install windows, the drive does not show up at first, but when i click refresh, the HDD suddenly appears but I am not able to install windows on it. I get an error. When i change ports to another located in the cluster of SATA ports, my BIOS sees the HDD connected. Can anyone help me get my computer running again. Im desperate!