Let me start by saying I'm not a computer wiz so bear with me. For the past few weeks while working on the internet my computer will randomly shut down. The shutdown occurs without warning or error message. I is preceeded by a loud humming noise then just turns into a black screen. The problem occurs sometime during the reboot if I try to turn the computer back on but if I wait 30 min to 1 hr it will work normally until it occurs again. The problem seems to be worse while TRYING to watch videos. Any help would be greatly appreciated.Hi there

Please provide us with more information about your system (see here)
Sorry for not including enough info. The computer is a Toshiba laptop that runs Windows XP, Pentium 4 CPUThats no problem

Which application do you use to watch videos & are they DVD's or files that CAUSE the crashes?

Unfortunately, it could be a number of different things causing your computer to crash. Unless you have anymore information you can think of that you can provide us which you suspect could have contributed to the problem, like the recent installation of software/hardware or any other problems/glitches you've noticed leading up to this problem, then we'll need to go through all the POSSIBLE CULPRITS (which isn't a problem).

First, MAKE sure you have all critical updates installed from Microsoft. Make sure after updates are installed, you check again & wait until you see the 'no critical updates are available...' message.

Then, do some basic maintenance. Download CCleaner & please read this guide for how to use it.

Also, check to see if your HD needs to be defragmented (guide here).

Next, see this guide for security software you'll need to download & also how to post your log files created by that software in the virus section for this forum.

That'll be a good start I think