Biostar x79 mbr missing after a couple weeks of running?

[deerfoot50]

After many, many years of building DIY systems this problem has me stumped.
Biostar X79 MOBO, i7-2011, Samsung 256 SSD primary, Raid 1 on 2 WD Black 1TB drives, 16GB Corsair 1600mhz memory.

System crashed after several weeks of running. "Missing boot device, insert boot media..." blah, blah. tried to re-installed Win7 Pro on SSD, couldn't find device. RMA'd mobo obtained another, installed new memory and upgraded CPU, changed SSD, unplugged RAID array... Fresh install with RAID drivers. Okay so far.. installed Intel chipset drivers, boot Win7 multiple times, no problems. Plug in RAID array, wham... won't boot "Missing MBR .... " Unplug RAID drives, boots up fine...

 

[o1die]

I've heard of this problem before when trying to use raid as a backup setup. Your ssd may be competing with the raid array when booting up. I would use only one of the drives instead of the raid setup when using the ssd as your main boot device. The problem isn't with the board, but with the raid driver.