computer just wont start!

hi

yesterday i just swapped my ISP aol to bt (i've got ride of my dads aol yey)
so my computer can have internet through a router i didn't install any software for it though as soon as i got on to the internet, i downloaded comodo personal firewall 2 from download.com.I insalled it and as usual it wanted to restart the sytem.So it stup down as usual then started starting up beeped once but nothing appered on the screen after about 20 seconds it beeped again as if tring to start again and it just repeats that.But i dont know what to do because i cant change any settings and i tried getting into the bois but it didn't work, i think it might have something to do with the new firewall or loading the internet for the first time. But i have no idea what to do because i cant do anythink software wise.what sould i do?

Thanks

So there is no VGA output whatsoever? It won't be a software related issue relating to the firewall because the problem is happening before the OS and software is loaded up.

yer no VGA output so wat could it be then?

i've tried putting a different hard drive in the machine with windows 98 on when booted it just did the same as the other hard drive

So, you dont get a picture when you turn your computer on?

i didn't
the problem was it was recalibrating and i left ther old graphic card in it when installed the new one
thank anyway