Computer cord I am looking for a cord that goes from the projector to the computer.

You are a teacher, and you don't know the difference between a chord and a cord ? Amazing. I think anyway you mean a lead - the one you require has a plug on one end to fit the projector, and a plug on the other to fit the camera. Look in the respective manuals.

the cords are usually fairly generic, large three pin like a computer tower no problem. If a odd shaped one go looking by model number on the internet, the older the set the more generic the cord will be.

Does the universal cord go into the rgb1 , rgb2 or S video input.

if it's the rgb input, swap to the other rgb input.
otherwise borrow a cable from the neighbours computer and try that.

if the wiggling is still needed then that socket on the LCD has dry joints on the pcb inside

You ca get one here: http://online.projectordoctor.com/InFocus-LP70_2 for $99 or try ebay.

check that you have a signal going out of the monitor socket on your lalptop.

On Dell with projector connected and switched on, press the blue fn button bottom left usually, and while holding, press one marked CRT/LCD, (maybe f8) this will cycle to the following.
laptop only, laptop and monitor, monitor only, while holding Fn button press until you have desired outcome.

hope this helps.

make sure the resolution matches. the projector resolution only goes up to 1280x1024

You're going to need a conversion dongle that goes from the Mini-DVI to VGA.

Then:

1. Connect one end of the projector signal cable to the Video Graphics Array (VGA) connector on the projector.
2. Connect the other end of the projector signal cable to the Digital Video Interface (DVI) connector or VGA connector on the notebook computer and tighten the screws.
3. Connect the projector power cord to the power cord connector on the projector.
4. Connect the other end of the power cord to an electrical outlet that is easily accessible and close to the projector.
5. Turn on the projector first, then turn on the computer.

Hello,
In the projector's menu under "sources" make sure that the box to the right of "Computer" is checked. Also check the box at the bottom of that page that says "auto source select" or something. But it is the last thing on that menu and should be checked.

Cheers

try to replace the power cord and see if it makes the noise again.  if it does, then there might be something wrong with the acutual projector, that I wouldnt be able to help you with and you might want to worry then.

power supply or lamp ballasts, both are pretty common to produce results as you describe, looking at $600.00 or so to repair. if those are the only things wrong.