My Laptop is Buzzing!!!

I have a Compaq Presario 2500 laptop, so I've had it for going on I think 5 years now. A couple of weeks ago I noticed my laptop started making a periodic buzzing noise. Sometimes it will stop for a minute or two, but for the most part it persists. I'm not sure if this is connected to the problem, but at the same time this started happening my battery life greatly decreased, so if I fully charge it and unplug it I only get 15 minutes before it dies (I used to get an hour before the buzzing started)

A friend of mine said I might have a bad capacitor, but I have no clue. Anyone have a suggestion!?

 

Try a different battery? If you have a spare, or can borrow one from someone that is compatible with your laptop, switch it out and see if it buzzes.

That or remove the battery, connect the laptop to AC power only, and see if it continues. If it does, it's probably something internal.

 

Is it running hotter than normal when it is buzzing?

 

Also what's the processor load? I've got a similar problem on my dv9308nr which makes a buzzing/squealing sound. I'm convinced that mine is related to the fan, but I won't know until I replace the fan and the processor next weekend.

 

Or it could be the hard drive, that's happened 3 times on my zv6000, and each time it resulted in a new hard drive for me.

 

I don't think so. It has always run pretty hot but I don't notice it running any hotter when it buzzes.

 

OK, so my laptop magically stopped buzzing yesterday for the whole day and most of today. However, now instead of the periodic buzzing it is a more constant buzz that lasts for a few minutes at a time.

I think when I just moved my screen a bit up or down it made the buzzing stop.
(Sorry I know I'm a noob with this stuff) Does that mean there might be something wrong with the connection in the screen or something?