I have a 2TB WD_BLACK SN770 that I've used for roughly five years. Recently, it has started disappearing intermittently during startup or while I'm using Windows. When it vanishes, it doesn't appear in Disk Management and rescanning for drives does nothing. Reseating it and moving it to another M.2 slot seemed to help temporarily, but the problem has returned. Restarting the computer sometimes makes it reappear, though it can disappear again later.
The drive still appears in the BIOS when the problem happens, and when Windows detects it, its health tools report around 96–100% health. A short diagnostic test also passed. The management software says there is a firmware update available. Is the SSD failing, or could this be caused by the M.2 slot, motherboard, firmware, or Windows? What should I check, and is it safe to update the firmware?
3 Answers
Install the manufacturer’s current storage-management utility and check the exact firmware notes for the SN770. A firmware update may improve compatibility or stability, but make a complete backup first and avoid interrupting power during the update. The reported 96–100% health only indicates that the drive’s recorded wear and SMART attributes look normal; it does not rule out an intermittent hardware or connection issue.
First, copy anything important off the drive while it’s still accessible. SMART health percentages and a short test can look fine even when a drive has an intermittent connection or controller problem. Check whether it appears in the BIOS when Windows loses it: if it disappears there too, suspect the SSD, M.2 slot, or motherboard; if the BIOS still sees it, Windows, drivers, or storage management may be involved. Reseat the drive, check the mounting screw and contacts, try another M.2 slot if available, and update the motherboard BIOS and chipset drivers.
It does still show up in the BIOS when Windows fails to detect it, so I’ll focus on drivers, firmware, and testing another slot after backing everything up.
Don’t rely on a bad-sector scan as the first step, since repeated scans can put unnecessary stress on a questionable drive. Back up the data, record the drive’s firmware and SMART information, then isolate the cause by changing one thing at a time: reseat the SSD, use another slot, update the motherboard firmware and chipset drivers, and test the drive elsewhere. If it keeps disappearing across different systems or slots, replacement is the safest option even if the health reading still says 100%.
Passing the short diagnostic is reassuring, but it isn’t proof that the drive is reliable. If the issue continues after the firmware update, test the SSD in another compatible system or test another known-good NVMe drive in the same slot.