Firstly, I don't know any of the lingo, so bear with me. I have a Gateway Solo 1150 laptop that worked great for years--it is an older one. I came to the conclusion somehow that my hard drive needed to be partitioned(that may be misspelled), so I thought I knew enough to do it myself. We moved, and I didn't have the time/space to work on it, so it went into storage. It was away from extremes and in a safe place, though. When I took it out tonight and turned it on, nothing. I heard the fan kick on and the disk drive light came on, but the screen was black. I tried an external monitor also and it was black too. Before, it atleast would load the gateway screen. I tried after taking the disk out(in the past that had been a prob), and then I tried to see if any of my disks would work like they had before, but no. Sometimes the power will go off, but not always. I also removed all the parts I could think of and replaced them. I do have another laptop that works OK, but the problem is I had given the gateway to my sister... and she will be pissed if I give it back to her after all this time in worse condition than it was when she gave it to me to fix. If anyone can help me stay out of trouble, I'l appriciate it. I know it's not a whole lot of info, but please feel free to ask if there is anything in particular that could be usefull. Thanks in advance.

I'm not too sure how to help, but there are multiple things that could've happened. For one, the video card might be shot. That would explain the lack of monitor screen. Second, the power going out might be due to the battery simply being too old. If you replaced both of those things and it still has the same problems, it's probably the motherboard (the main control unit of the computer) and so you're simply stuck. Best to get a new one or buy an older laptop for your sister.

Try runing on AC power if that wont work it might be the motherboard

I have fixed lots of the Solo laptops.
When I need parts I search Ebay where the 1150's are going for
US $30 to 50.
The laptops like so many other things don't like being put away for any length of time, it's use it or lose it, like cars, boats, and motorcycles.