The battery on this laptop is removable from the outside (without disassembling the rest of the laptop) and the laptop has worked perfectly fine without the battery and just external power in the past. Also, when I power on the laptop, the power button and some other LEDs light up (doesn't matter if just the battery, just external power or both) - so that's still working fine, I guess. Or is there something else I need to check?
Since we're now doing more general troubleshooting, I guess imma start from the ground up with the problem I have.
The laptop was running normally before. But when I turned it on a couple of days ago, all that happened was the fan turning on, some LEDs lighting up and a blinking white cursor immediately appearing in the top left of the otherwise completely black screen - before it got to windows or even the BIOS. I opened the laptop to look at the mainboard but couldn't find anything that looked bad. While I was at it, I also repasted the GPU and CPU. Then I put isopropyl alcohol on the entire board and turned it on, because the alcohol should evaporate quickly if there was a short anywhere - nothing unexpected happened though. After that, everything was still as before.
Then I connected to the BIOS chip, read the BIOS off of the chip and saved it on the RPi. I downloaded the BIOS from the Asus website and wanted to flash it. I got an error because the file was not the same size as the chip. I looked around in the internet but couldn't find anything useful. Thinking I could just flash the old BIOS back to the laptop if anything goes wrong, I decided to just create an empty file the size of the chip and put the downloaded BIOS at the beginning of it and then flash that file. Turns out that thats not the way to do it - when I turned the laptop on, it was again just some LEDs lighting up, but this time the fan and the screen stayed off. So I flashed the old BIOS back, but nothing changed... still just the LEDs lighting up, no fan spin or image on the screen. So if the BIOS didn't have a problem before, it might now have one...
Any help would be appreciated, though I would definitely understand if you dont want to anymore