One of the slave hard drive isn't recognized

[oekoeloe]

Hello!

I installed my new motherboard yesterday (Gigabyte z97p-d3)
I have 1 hard drive that has a newly installed Windows 8.1
And 2 slave harddrives and 1 of them isn't recognized by the computer at all.
All the cables are good, I double check with other cables and sata slots.
The hard drive doesn't show up on Device manager and diskmanager.

What can I do to fix this?

 

[aldan]

i know youve said you have tried other cables and slots,but have you tried plugging it into the cable from the hdd that is recognized?

 

[oekoeloe]

i know youve said you have tried other cables and slots,but have you tried plugging it into the cable from the hdd that is recognized?

Yes I tried.
Just now, instead of turning the computer off, I rebooted it and now it is recognized :S
I'm making a backup of all the files on it now that I have the chance