How to diagnose a failing SSD?

[sling-shot]

I have a M2 NVME SSD containing the main OS and data. I also have other HDDs with secondary operating systems. Recently computer freezes at random times including while in the BIOS or pre-boot, requiring the press of hardware reset button to bring it back. On reboot, the SSD will have disappeared from the system. After a day or two it seems to reappear and will work normally until it does this again.

When working SMART status does not indicate any error.

How do I determine if it is an SSD failing symptom or motherboard issue? What would be best to do right now?

EDIT: If I decide to replace it will Crurcial T500 be a good option or P3 is good enough? Is the heatsink essential?

 

[Desmond]

Install CrystalDiskInfo and check the SMART values.

It's also likely that the drive has loose connection?

 

[patkim]

Since you have multiple storage devices (SSD + HDD) and multiple OSes (Assuming no dependency on other disk for booting), consider connecting one at a time and observe the outcome for a few days.
As far SSD is concerned, if it's from good brands, then the vendor should have monitoring apps (e.g. Samsung Magician, ADATA SSD Toolbox like that) to check the SSD for SMART as well as overall health. So do try those.
Re-seat the drives in respective SATA/M.2 ports.
If the system freezes while Windows is running then it will likely add details in the Event Viewer. See if anything meaningful can be derived from it.
In case your motherboard has 2 M.2 ports supporting PCIe NVMe, then try shifting the SSD to another slot and observe the outcome for a few days.

I have noticed that generally M.2 PCIe Gen-4 Slots on mobo come with preinstalled heatsink. However Gen-3 generally are not.
I have Samsung Gen-3 NVMe SSD and it would heat up to 50 C in summer. So I simply added Silicon thermal pads on it and then temps came down to 44 or so!

 

[sling-shot]

Heating may not be the issue as this is sometimes observed in BIOS soon after boot. Still it could be one point to verify.

I will do a clean contacts and reseat and check.

It is a Crucial SSD.

SMART values were normal last time I checked after 3 or 4 such episodes. This happened while Windows was running once or twice but long back so will wait for next episode.

It is Gigabyte B450 motherboard, I think there is only one slot.

 

[patkim]

Check if this proprietary tool from Crucial helps -> *www.crucial.in/support/storage-executive
Install and see what all monitoring options are available.