I m having the exact same problem, having cloned my HDD to SSD and attempting to replace the unit in my Latitude 6420 -- following the swap, I keep getting this screen:
"No boot device found. Press any key to reboot the machine,"
following the preceding messages:
"PXE-E61: Media test failure, check cable,"
"PXE-M0F: Exiting Intel Boot Agent."
Max, did you ever find a way to resolve this issue? I would be grateful, as the replies below don't seem to address the problem I am facing.
Many thanks -- to anyone with feedback here!