Sata2 Port Switch on Boot

Hi
Curious issue with an aging ASRock 980DE3/U3S3 on a W10 rig.
Yesterday, turned the machine on with the two IDE disks listed as per usual on the boot up screen, showed the Windows logo, rebooted, and got a Disk Read Error, Ctrl-Alt-Del to reboot message, at which stage the keyboard was dead.
Powered off, on, rebooted and Windows came up as per usual, no errors in the logs. Later ran a quick scan of the drives in SeaTools, no errors, so no change in the drive performance histories.

Today, the boot errors were a bit different, this time the boot followed by self reboot was followed by the well known preparing automatic repair message, with the keyboard also dead. So rebooted, and went into UEFI to check the disks, where it reported the IDE drives as not detected! Then the program/keyboard froze, so a a hard reset was the only way out.
Consequently, it was navigating into the boot order section to discover the primary boot device was now AHCI-P0! No SSDs or other AHCI devices attached in living memory so how did that happen? Changing the primary boot device to the first IDE, Windows booted up as if nothing had happened.
Is it expected that aging motherboards can be somewhat unpredictable in operation, and is it a sign of pending EOL?
Thanks.

Each power on, the machine either

* Boots, shows the Windows log, freeze/lights out on keyboard after 2-3 secs
* Boots, shows the Windows log and "Preparing Automatic Repair", freeze/lights out on keyboard after 2-3 secs
* Boots, shows black, then reboots
* Boots with the errors in the previous post (with less frequency)

Also, when navigating the UEFI menu, there's always the possibility of instant freeze.

The most unusual effect of all this, is once the machine boots up into Windows, everything is just fine, for hours on end in fact.


Can it ever be ascertained from the above as to what component on the mobo is failing?

@TommyLich, hi.
Sorry to hear about the no mouse/keyboard issue.
Related thread: https://forum.asrock.com/forum_posts.asp?TID=15157
These things sound as if there is bad communication between UEFI and Windows.
Funnily enough, the problem over here has gone away, ... for now. All the same, gone down the rabbit hole of a bootable live Linux USB stick - the first choice was Oracle Linux BootISO, wasn't sure if that was possible for a 16GB stick, so instead set up a Puppy Slackware64 15.0 boot instead. Not guarantees it will help, as there can be issues like these:
https://forum.puppylinux.com/viewtopic.php?t=3220
Puppy have a lot of good info & help at their forums.
The point of the above exercise can be a little lost, since it won't help Windows much, and any UEFI glitches are probably better dealt with a separate UEFI shell like this:
https://github.com/pbatard/UEFI-Shell/releases