So, (I feel ashamed as I've had this problem for a good 7 months) in Christmas 2015, I built a gaming computer with help from folks at my nearest big computer store (everyone there is very knowledgeable, all their computers run on a modded command line operating system that networks with the other computers and even has built in BBS with their closed network), and I used a GIGABYTE GA-F2A88XN-WIFI motherboard and a Seagate ST1000DM003 1000GB Desktop HDD, and around two months of owning the computer, the BIOS randomly stopped detecting the HDD. Most of the time it wouldn't detect the HDD, but sometimes, with no apparent reason why, it will work fine. I have switched out the two 6 Gbps SATA cables between the HDD and my DVD Disc Drive, and there was no improvement. I tested both the cables, as they never fail on my Disc Drive, and a while ago I took my computer in to the place I built it, it's called MICRO CENTER, and they said the drive was passing the smart test, but they also said there was no data on it. I decided that it must have wiped itself, and I put it away, as I thought I was going to use my 2-Year Warranty and send it back for replacement. Today, after my grandfather, who is a retired computer engineer, my friend who took a year long college level class on computer engineering, and the person who analyzed my HDD at MICRO CENTER all said that I should just try using it again, and if it wiped itself again THEN send it back, I decided I should take their advice. I hooked the HDD up, turned on the PC, and the HDD showed up in the Boot Menu. I booted it up and there was no data gone, contrary to what the guys at MICRO CENTER said. I was really happy for a while, until my audio stopped working, so I decided I would reboot, and when I tried to reboot my HDD was not being detected. After hours of stress and switching SATA cables, I'm about ready to give up. Can anyone help, or point me to someone/somewhere that can?