So I know you shouldn't do this (and I'm gonna stop from now on) but I've been shutting down my PC by holding the power button and not shutting it down properly - and I think this is the reason for my problem. A few days ago I started up my computer and then after I had been on the internet for a while it just rebooted itself. So I kept starting it up then when everything had loaded it just kept rebooting. Now it doesn't even load up it goes to a black screen that says something about CMOS checksum error - Defaults Loaded. I've searched for other people with this problem and the responses tend to be to do something with the BIOS (sorry, I'm not very technical. I don't even know what the BIOS are) but my problem is my keyboard has now become unresponsive that I can't get it into anywhere to change the settings. When I start up all the lights come on for a second (num lock, caps lock and scroll lock) but then go off and my keyboard becomes unresponsive. Then when I try to reboot the computer from the power button it doesn't even start up now! (It's just going from bad to worse) Like it turns on (I think it's the fan that makes a noise?) but nothing happens the screens black, it doesn't even make that beeping noise it usually does when it's just starting to start up. I have to wait for a while (like a good few hours or even a day) before I can try and start it up again and it will go to the CMOS checksum error screen. Please help! And, if possible, please put things as simply as possible as (maybe you can tell) I'm not very technical.