When my keyboard lost the ability to produce a comma, which also lost me the left angle bracket (<) I thought I'd be forced to abandon my computer and simply move the hard drive to a new computer of the same model. (Which I'd gotten for parts to fix my computer.)
Turns out... no. At first I thought the thing wouldn't start. After opening it up I discovered that the problem was more... problematic. Instead of being plugged in the monitor cable was shoved into a place in which it did not fit warping the metal housing around the circuit board and having to be pried free in ways that almost certainly did real damage to the computer.
In hindsight I should have just cut it and left it wedged in there. I by the time I got the cable out it was visibly fucked. Thankfully I had a brand new cable I'd gotten when I was hoping that my original cable was what caused the red to go away.
So I installed the screen from the new computer, and the keyboard (which isn't quite perfect, the end key is in the process of being reattached. The good news: A working computer that needs only two screws that don't belong to it and doesn't have a cracked screen and such. The bad news: Red still doesn't work. It's not the monitor, it's not the cable, against all the odds it's something wrong with the computer itself. In fact I think we can narrow it down to one part of the computer. If I plug in an external monitor cable that will work, red and all. So it has to be the socket thingy into which the LCD cable plugs or something leading to that that is responsible for the lack of red.
Also, certain letters on the keyboard stopped working while typing this, then started working again. So... no fucking clue. I may need a new primary computer. I have a new secondary computer, thank you Ana, but it doesn't do DVDs and CDs.
[Added:] Ha, ha! Mine is a triumphant laugh. "End" key reattached, if a bit wiggly.