I have a librebooted Lenovo T400 laptop which I picked up on Ebay a few years ago. I went to turn it on for the first time in a few weeks and, to my great disappointment, the screen did not turn on. I did some research and determined that the culprit could be the RAM. The laptop came to me with a spinning hard drive and 4 GB of RAM (2×2). I replaced the hard drive with a solid state drive and doubled the RAM to 8 GB (4×4). The laptop’s screen powered on when I removed one of the new RAM sticks. I got rid of the broken RAM and re-inserted one of the original 2 GB sticks of RAM (so we now have 6 GB total) while waiting for a new order of two 4 GB sticks. I also ordered new case screws since I have a few missing screws and two of the screws that were holding the palm rest seem to not fit correctly. At least it works, I suppose.