After a bunch of frustrating issues at install with my BIOS not recognizing one or both of my drives (see sig for specifics) - I managed to get windows 10 pro installed on my SSD and boot into windows. Unfortunately, I am having the same issues once windows has been installed where my BIOS doesn't recognize my SSD and therefore will not boot into windows. I have checked the drive with Samsung magician and it is "good" according to the tool and the system operated fine for the 3 or so months since my initial build at the end of 2017.

I have seen a couple other posts with similar issues but they didn't seem to resolve ( http://forum.asrock.com/forum_posts.asp%3FTID=5401&title=ab350m-pro4-ultra-m2-slot-not-working960evo" rel="nofollow - http://forum.asrock.com/forum_posts.asp%3FTID=5401&title=ab350m-pro4-ultra-m2-slot-not-working960evo ) - does anyone know what is going on or how this can be resolved?

I am also noticing that my BIOS settings seem to be changing without input from me - most notably my CSM which was mentioned in the post linked above. No idea what is going on and it is immensely frustrating. Any suggestions/thoughts?

Just one other observation: it's generally considered best practice to have only one drive connected when installing Windows, then add any others afterwards.

I did end up re-installing my OS by removing my HDD so I think I got that right at least.

Eventually I can get the BIOS to recognize the SSD it just takes some tinkering with settings and reboots. If the computer is left on, eventually it seems to re-boot but I don't know if that is windows restarting or what exactly.

Changing the CSM settings and plugging in a boot disk seems to occasionally allow me to boot from my SSD but it is inconsistent (inconsistent insofar as the BIOS recognizes the SSD and boots to windows).

Any other ideas on what I can do to resolve this issue?

What could possibly be causing this issue?!

Tinkering with the CSM settings seems to get a favorable result (i.e. it boots to SSD) but it is not repeatable/consistent.

I finally got my BBS set to use the SSD as the primary boot drive but then I noticed that it was disabled as shown in the image here -  http://imgur.com/a/Y1e9q" rel="nofollow - https://imgur.com/a/Y1e9q

Is there some hidden setting that is causing my SSD to be disabled? I also occasionally fail to boot even when I get the BIOS to boot from the SSD. It almost seems as if the drive is bad but it shows up fine using Samsung Magician.

So far, it's not looking like there's a good fix aside from throwing the ASRock mobo in the trash and buying a board from a different manufacturer... hardly an ideal solution.

I've put in a ticket with ASRock support for my issue. Have you put in a support ticket yet? Maybe if we get all of these SSD issues in their ticket queue, they'll realize they have a problem and actually fix it.

https://event.asrock.com/tsd-networking.asp

I just don't understand at all how it is not repeatable in any way. The exact same settings will seem to produce different results which makes even trial-and-error troubleshooting impossible.

I'll submit a ticket to ASRock but I imagine a replacement will be necessary to resolve the issue. Any idea what would provide similar functionality as the AB350 pro4?

I cannot seem to get repeatable behavior from my system. Will set BIOS settings and boot to Windows fine one day and then the system will fail to recognize my drive the next day. Will tinker with settings sometimes just rotating through the same CSM settings until it boots.

I can't for the life of me figure out what is causing the issues and will likely just try to replace my MoBo if I don't figure out something soon.

I am kinda new to CPU builds (this is my first one) and I just feel kinda paralyzed at the moment with no real direction to move forward and a ~1200 dollar paper weight on my desk :(

Thanks again for any help/support you can provide