I am facing a peculiar problem in windows 7 which is causing me great frustration and anxiety, besides forcing me to throw money at upgrading. Here are the PC configs (see in my signature too): core i7 920, MSI X58M motherboard, 700W Coolermaster Silent Pro PSU, CM 692 advanced chassis, combination of WDC and Seagate HDDs (all relatively new with the oldest one being of 2009 vintage). The problem: 1. in windows 7 64 bit enterprise, hard disks (and their partitions) suddenly go missing. Can happen to any hard disk incl. the boot hard disk but seems to happen more in WDC. Say 23 out of 25 times has been with WDC, and 25 out of 25 times in windows 7 (not in xp which I was using till Feb 2010). Have 2 TB CB, 1 TB CB, and 2 WDC Greens. The primary 2 TB WD CB bought in Oct 2010, the 1 TB CB in Sep 2010, and the Greens also recently. Seagates are also 2009-10. One hard disk missing can be dismissed as hard disk fault, but multiple hard disks??? 2. first solution is restart, and BIOS often does not detect it, or hangs, or takes a long time. When it finally loads into windows (assuming of course that it is the non-primary disk that has gone missing, disk rescan in computer management is of no help and cannot be relied upon). Anyway that is useless, if the disk that has gone missing has windows on it. 3. the solution that works is shutdown the PC, open the chassis, take out and replug the SATA cable (in the disk that has gone missing) and in 100% of the cases, this works. Reboot and both BIOS and then windows 7 detects it. That is till the next time, when the same or some other disk goes on its missing in action thing. This happens only in windows 7 environment when I am working. Have tried all sorts of solutions, new SATA cables, etc but no end to this. Even have removed 1-2 Seagates so that my internal box is loaded with WD only. Will driver updates help (doubtful if it will help) or BIOS update/flash (not keen) or BIOS settings change (easy) or some other trick. Is there a fix as it can be very frustrating to open the box every few days and replug the SATA cables.