Hi all.

I have 2 boards of Dell XPS 13 9370 (Compal LA-E671P) that had a same problem after replacing processor.
Their run perfectly on battery, but had problem when it connected to USB-C PD charger before load windows.
If I connect a charger when the laptop was off, then I tried to turn on, their had bootloop. Only show Dell Splash Screen, and restarted.
Cannot load windows, cannot load Dell diagnostic, but can enter bios.
If I removed a charger (only batteries), turn on, it can load windows or can load Dell diagnostic perfectly.
In windows, if I connect a charger, it can charge the batteries to 100%, no show error.

1st Board :
Came originally with the laptop that have random BSOD on windows especially "Watchdog..". Check RAM with memtest86, all passed. Had no error with charger. It can load windows with/without charger.
So I decided to replace the i7-8550U (SR3LC) processor. After replacement, I flashed clear ME BIOS, set BG to 0, and get the problem with charger connected before windows load.

2nd Board :
Board that I bought on Ali. Came with i3-8130u (SR3W0) processor. When it's arrived, I had checked everything, of course the charging too, it's 100% normal. Had no error with charger. It can load windows with/without charger.
I deciced to try to replace the i3-8130u (SR3W0) to i7-8550U (SR3LA) processor (another processor, not same processor that I plant on 1st board).
After replacement, I flashed clear ME BIOS, set BG to 0, and get the problem with charger connected before windows load (same problem as the 1st board).

Donor Processor for 1st Board it came from Lenovo Yoga 730-13IKB (Compal LA-F571P, checked BG = 0)
Donor Processor for 2nd Board it came from Lenovo Yoga 720-13IKB (Compal LA-E551P, checked BG = 0)

Is there must a special treatment after replacing processor for this board??