My SATA hard disk stops getting detected after booting. Sometimes it is getting detected and most of the times not. When I turn off the PC next time then it detects for some time and then again vanishes after 5-10 minutes.A technician worked on it and said that in his shop, it is working fine. I have already exchanged the hard disk, SATA cable, new power cable, tried with all SATA ports on the mainboard. Initially the technician pointed to a earthing issue as the PC was giving light shocks but I have also tried with a different main plug and there it was not giving shocks. Any help would be appreciated.