I am a novice and huge beginner. I bought a prebuilt PC without a graphics card. I bought and installed a video graphics card. I added a half GB of RAM from an old Dell to the 2nd RAM slot, turned on the computer a few times (before I had a working DVI adapter) and decided this might mess up the computer, so I took it out. Then I got the adapter in the mail and used it and the computers been working fine. The last time I started it, yesterday, the BIOS set up screen appeared. I just hit save and exit and went on my day. I used the computer for several hours and it was fine.Today, I started it and the fans started and stopped repeatedly and the monitor wasn't detecting anything. I turned it off. I did some research online and decided to remove the motherboard battery for 10 minutes with the power off. It was a vertical battery standing straight up. I forgot to check which way was plus or minus. I put the battery back in. I turned on the computer and theres a red light thats shining on the motherboard now, the fans work, but the monitor won't detect anything. I thought maybe it was in the wrong way so I tried it the other way. Same red light. Pic: http://i.imgur.com/bZBoucT.jpg
The monitor is brand new and works fine so it's not the monitor. The rest of the night has been me looking up stuff online to no avail. Most of it is too complicated for me to understand. Im scared maybe I damaged the battery. Other things I've tried: making sure the RAM is firmly in. Switching RAM slots. Switching back. Plugging and unplugging power into motherboard