XPS 15 will not boot to anything other than USB

I've been having a issue with this computer for the past month. It will not boot to windows with internal drive at all. the only way I can get it to work is if I plug in a external hard via USB and boot to safe mode.

When I plug in the hard drive normally via sata it gives me a black screen saying no bootable devices were found even when pressing f12. Its not a problem with Windows as I have tried clean installs which I know are working

The bios says that there is no primary drive installed but I can still browse the files via boot options and command prompt??? (note screens hot) (Sata 0 is the 32gb m. 2 which has nothing installed on it)
I have tried different drives with no avail. I have also attempted to install windows to an m.2 which didn't work. I tries taking out the m. 2 which didn't work either

My guess is something in either the motherboard or the firmware has screwed up maybe

Any suggestions will be appreciated

 

Try resetting BIOS defaults.

 

I tried that. Still gives me the same problem

 

Normally fixes most evils of this laptop, have you tried flashing the BIOS again, downgrading the BIOS (or upgrading)

It is very strange a clean install didn't help, have you tried pulling the 32gb to leave the drive for windows as the only option?

Only other thing I can think is a corrupted boot path being installed on either the external ( I know a million to one chance right? ) or the 32gb having the boot path hence reinstalling to the other doing bugger all.

Maybe try the clean command with fdisk?

Also did you try both BIOS defaults, as it offers 2 choices?

 

I thought for sure any XPS I had with a 32gb cache drive showed up under the m.2 slot. Maybe it's just a bad cache drive? Is your laptop under warranty? Maybe you should take it out and reseat it?

*on edit* I just fully read what you wrote. I'm not sure where the 32gb drive showed up then. Is your sata drive a HGST? I've only ever seen WD drives in mine.

 

Disconnecting or disabling the cache drive doesn't work either. I reckon have attempted just about every software fix there is.

I suspect there is something fishy going on with the firmware of the drive controllers because no drives are detected in ahci mode and only the m.2 cache drive is detected in raid even though the Dell diagnostic software says both drives are connected.
It makes a coil whining sound when trying to read from the drive which is strange
I tried flashing the latest 1.2.21 bios when I first had the issue to no avail.

I would send it back to Dell but I bought it refurbished from a ebay seller though it is still under warranty I'm not sure they will accept it

Hope its not £700 down the drain

 

You can transfer the warranty on it - https://www.dell.com/support/assets-transfer/us/en/19

 

Did you do the fdisk clean command on the cache drive in raid mode?

Sent from my SM-G920F using Tapatalk

 

Deleted

 

Sorry for the late reply currently I am in the middle of some important exams.
I have tried a secure erase of the ssd I'm not sure if that accomplishes the same thing

 

yep same thing

 

It turns out it was a faulty motherboard for anyone else having this issue