Question Dell Latitude e7470 bad behaviour

[dungbv]

I have a Latitude e7470 (i5-6300u, 8GB RAM, 250GB SanDisk M.2 Sata drive, 1366x768). Recently, the laptop behaves strangely. After some days not using it, power up it and it still boots to Windows. But black screen before login hangs for a few minutes, then the system reboot and says "No bootable devices found". If I force laptop to turn off (Holding button for 5sec), it boots to Recovery and if I choose restart, Windows will boot normally. Also after long time sleeping or hibernating, the laptop will crash at login screen and doing the same thing. Tried to update all drivers, BIOS to newest but it doesn't help at all. My Windows 10 is clean-installed. Maybe it has to do with the BIOS? If BIOS downgrade is possible, can I do that? My SSD, RAM is fine, connected to mobo properly.Please help me! I'm so frustrated.
Edit: Also there is a eratic touchpad/trackpoint, but I can skip it because I'll disable it and use external mouse anyway

 

[Aeacus]

My SSD, RAM is fine, connected to mobo properly.

Just because you have hardware connected to MoBo, doesn't mean that they are fine.

Based on symptoms, i'd get new SSD, since yours seems to be it's way out.
Also, as long as you do not try with 2nd, known to work SSD, you can not rule out SSD failure.

 

[dungbv]

Just because you have hardware connected to MoBo, doesn't mean that they are fine.

Based on symptoms, i'd get new SSD, since yours seems to be it's way out.
Also, as long as you do not try with 2nd, known to work SSD, you can not rule out SSD failure.

Thank you. I tried another SSD and RAM module, they worked.
Edit: Problem is still there

 

[Aeacus]

Did you make clean Win install with 2nd SSD?

 

[dungbv]

Did you make clean Win install with 2nd SSD?

Yes

 

[Aeacus]

"No bootable devices found"

3 reasons for that:
1. OS is corrupt - clean install usually fixes it.
2. SSD is toast - new drive fixes it.
3. Mobo is toast - MoBo replacement. <- Now, if your MoBo has 2nd SATA slot, you can try that one, since most laptops support 2 drives. Could be that the SATA port on MoBo is iffy.

All-in-all, symptoms show some kind of hardware flaw, where it takes for laptop (MoBo), far longer to make sense of all of it, before MoBo is able to get the system to boot to OS.

You have quite old, Intel 6th gen laptop and i'd retire it completely. But if you want to get some life back to it (or to have more hope in doing it), i suggest that you bring your laptop to PC repair shop and pay them for diagnostics + fix.

 

[dungbv]

3 reasons for that:
1. OS is corrupt - clean install usually fixes it.
2. SSD is toast - new drive fixes it.
3. Mobo is toast - MoBo replacement. <- Now, if your MoBo has 2nd SATA slot, you can try that one, since most laptops support 2 drives. Could be that the SATA port on MoBo is iffy.

All-in-all, symptoms show some kind of hardware flaw, where it takes for laptop (MoBo), far longer to make sense of all of it, before MoBo is able to get the system to boot to OS.

You have quite old, Intel 6th gen laptop and i'd retire it completely. But if you want to get some life back to it (or to have more hope in doing it), i suggest that you bring your laptop to PC repair shop and pay them for diagnostics + fix.

Well maybe no3 is true. I'll bring it to repair soon. Thank you.

 

[dungbv]

I can't believe that the mobo's DIMM A slot is faulty. Put the RAM to DIMM B slot, everything is normal now (Not sure why 'No bootable devices found' disappeared).