SSD sometimes NOT detected while boot

[VagelisGr]

Hello. I have a problem with my new build. Sometimes especially after cold boot my ssd Crucial MX100 256 is not detected in bios. After post screen it goes back to bios and in boot priority category it shows only me WD Cavial Black 1Tb. Its been six months since I built my computer. I have this problem the last one month. I will list down below my specs and the solutions I have already tried. 

ASUS Z170A
i7 6700k 4ghz
kingston fury 16gb ddr4
GIGABYTE GTX 970 G1
Coolermaster Silent Pro M850W
Crucial MX 100
WD Caviar Black 1TB

1) I changed sata cables for both my Hard Drives
2) I changed sata ports again for my both Hard Drives
3) I updated my ssd firmware to the latest
4) My motherboard's bios is also up to the latest version.

P.S:I marked that issue after Ι updated 1300 version and then. I mean the first months this problem never existed. I dont know if this is just a coincidence or this problem exists due to bios issue. I downgrated to 1200 version and it seems to work fine for now. The problem is that after 1300 version they solved the problem with Skylake bug and prime 95(update micro chip code as I remember).

Have you ever experienced something like this guys ? Anyone with ASUS Z170 Board? 
SORRY FOR MY ENGLISH GUYS. I hope you understand what I want to say! Thank you!

[SirBobson]

I might have something similar to you but I don't have a z170 board. I just posted a topic about it as well: 

 

[VagelisGr]

1 minute ago, SirBobson said:

I might have something similar to you but I don't have a z170 board. I just posted a topic about it as well: 

 

I hope we will find a solution soon. 

[Captain_WD]

11 hours ago, VagelisGr said:

~snip~

Hey there VagelisGr,

 

Good job on the basic troubleshooting with the cables and ports.

 

Since the issue seems fixed by downgrading the BIOS version I'd suggest contacting the motherboard's manufacturer's support and ask if this is a known issue or not and see what the guys there have to say about this. This seems to be the most apparent cause for the problem.

 

I'd still check if the PSU is providing proper power to the SSD and it's not the cause of the issue. Do you have both drives on the same power cable? I'd try to swap around that and see if there are any changes. 

 

Another thing that you can do is check the SSD's health. There should be a tool provided by the manufacturer that you can use to perform some diagnostic tests. You can also check the S.M.A.R.T. status of the drive and its raw values to get a better idea of the drive's health. Feel free to post them here if you have trouble reading them.

 

Captain_WD.