Location: Principal's office
OS: 98SE

Problem:
Last night (Tuesday) we did a Symantec update, meaning that all the computers were left on.
When the principal restarted his computer this morning, the computer only powered on, no visual on the monitor and just beeped.
This beep is about 2-3 seconds long and repeats its self ever 2-3 seconds.
BEEEEEEEEEEEEEEEEP BEEEEEEEEEEEEEEEEEEEP

I know that it is a Hardware problem, but where do I start?

Normally I would pull all cards except the video card and disconnect all drives

Try to boot in bare bones...

If it still beeps I would try and swap in a different video card...

Did anyone other than authorized staff have any access to the machine...?

Thanks guys. Figured it out!

wel a small idea from me: check all ur harware components, inside the cpu as well as the connections of the pheripherals,if still it comes to work, please carry out a virus check spyware. :)