I have an HP 640 g4 that doesn't give an image, the charging light only blinks 6 times. Unfortunately, I don't have the original BIOS since it was recorded by someone else and they didn't save the original.
Serial Number : 5CG8284NB1
Product Number : 3WW24LT
Description : HP ProBook 640 G4 ​​
Here is the BIOS that the device had, I don't think it's the original.​...