About a month ago, I received an error message that stated my computer did not recognize my AC adapter. It would recognize it after reinserting the adapter a few times and rebooting. If I powered off, I would then have to go through the whole process again until I was able to work off the AC adapter. Once I got it to recognize the adapter, I left the laptop on to avoid this issue.
Then about a week ago, while in Windows XP, my computer freezes. I tried to reboot with the AC adapter. The only thing that would happen is I would get a flashing cursor in the top left corner. If I took the AC adapter out and ran off of battery power, my laptop would attempt to load to Windows but locked up at the splash screen. My laptop will boot to safe mode from the battery. The battery will not charge though as if I ever attempted to use the AC adapter, my laptop would lock up immediately.
Can anyone say with any certainty if the problem lies in my motherboard, power jack, or the AC adapter? It is definitely not the hard drive.
I cannot say with certainty what your problem is. However, I have had to recently resolder my power jack. Apparently, the Inspiron 1150 is popular for failing power jacks. I took my 1150 apart and inspected the power jack. There was hardly any solder on the power jack pins! You may possibly have a bad power jack solder connection(s) like I did. I resoldered all the pins and my Inspiron is back in action. If you already have a soldering iron, solder, flux, and alcohol the repair is super cheap to try. It took me a couple of hours.
Thanks for the hint! Finally I found possible solution to the very same problem. I've been fighting with this "feature" already a while, bying new battery and memory chips. But nothing helped. I will check if my 1150 has the same problem with the power jack pins.