Strange boot behaviour

[Hoofcarver]

I am having a problem when booting my computer. Sometimes, if I power on it will get to the splash screen, but then falter and reboot, and when it reboots it will not recognize either of my M.2 SSDs. If I power the computer off, and then flip the switch on the power supply on and off, it will boot normally and seems to be stable. One thing I have noticed, is that sometimes when I navigate to my second m.2 in explorer, it can hang for a few seconds.

 

The problem seems to happen most repeatably if I shut down my computer (but not switch off the power supply) and leave it for a few hours and try and power it back on. Interestingly, if I reboot my system from a powered on and functional state but enter the bios, I can't see either of the M.2 SSDs in the boot menu. However, if I save and exit the bios after not seeing the disks, it seems to boot fine.

I recently changed a few things with my configuration including:

- moved the whole system to a new case (a Fractal Meshify)

- added a second m.2 SSD Which is a x4 NVMe running at x2 as per the motherboard spec

Anyone else have this kind of problem? I am looking for ideas of how to troubleshoot this.