My girlfriend just called stating that her battery is dead and wont charge. I told her to plug in the laptop and see if it runs just on the A/C adapter with and without the battery plugged in. No go.
I believe the issue is the sodering on her A/C adapter laptop receiver has come undone. The only thing I need to know is if laptops have a PSU in the traditional sense (like a desktop). I don't think they do as there is 2 methods to power the laptop and an internal laptop PSU would be redundant as the a/c adapter or battery serves as the PSU. Just wanted to see if that was the case, so I can proceed from there to get her laptop fixed.
I should just learn to soder in case something like this happens again.
Nope - the battery is DC (which is what all the components run on), and the AC adapter feeds the laptop DC. There are some components in the laptop to handle voltages and power to specific components, but no single "PSU" or anything like that.