SATA sockets 1 and 2 OK - SATA sockets 3 and 4 u/s

I have added a second SATA DVD drive to my Windows 7 Medion Akoya MD 7659 computer and it is not recognized in the BIOS or in Windows Explorer. When I reconnect this drive as the first DVD drive it works as expected thus eliminating several possibilities such as faulty power and data cables and connections.

The mainboard is an Micro Star MS-7707 as read on the board itself and confirmed by Belarc Adviser. As the SATA sockets 1 and 2 are active and SATA sockets 3 and 4 not active can anyone offer me some guidance please towards enabling sockets 3 and 4? In the BIOS SATA Mode is set to ACHI and also available are IDE and RAID modes but from my very limited knowledge of SATA modes RAID is not relevant and IDE will not affect the issue. I haven't tried IDE Mode yet being reluctant to do so until I have a better understanding of whatever the problem could be.

Any advice will be gratefully received.

I couldn't find any documentation on your board(s). (There seems to be a mis-match between your specs and the info in your thread.) Perhaps it's European only and/or OEM only. So, there's no telling what BIOS or controller is installed. The problem could be that ports 1 & 2 are on a separate controller than ports 3 & 4 and that controller is disabled in the BIOS or the drivers haven't been installed.

About all I can suggest at this point is to un-install the DVD driver for the drive that is recognized through Device Manager. Shutdown the PC, disconnect the power (turn off PS AND disconnect cord), wait 10 minutes then install the second DVD. Power up and see if Windows finds new hardware and installs the drivers.

If this doesn't work, you may have to reset CMOS memory. And, you'll have to follow the directions in your user manual for this. Some methods vary widely between PCs.