SSD keeps dropping out of the bios

I have isn’t 256 Ultra as my bootdisk. Whenever I boot it tells me that it can’t find the operating system and to disconnect other drives. However, when I hit Enter, it frequently begins to load Windows 8 as though there was no problem. Unfortunately, sometimes I have to keep resetting until I can get it to boot. I’ve gone into the BIOS and the SATA slot appears to be empty where the SSD is connected. I’ve tried swapping ports and SATA cables but have the same problem.

This is a new build using a GA-Z87M-D3HP Motherboard. I’ve updated MOBO drivers.

Is the problem likely to be the SATA controllers or the SDD . . . or something else again.

Clearly I was having a dopey moment. I had the SATA controller set to IDE instead of AHCI. Changing it over and reinstalling Windows fixed the problem.