Compaq Laptop problem, need help please

i have a compaq laptop and when i press the power button, the light comes on but nothing will come on the screen, (do not think its a screen problem) as at first i was able to push down hard next to the mouse pad and it would start working and try to load up, it would start to load up for a few seconds then freeze, so i can see on the screen the frozen image so i would try to push down next to to mouse pad again and it would load again for another few seconds, this was a few weeks ago but now when i try when i push down on it again i cant get it to load anything anymore, so all i get is the power light on and a black screen,so when i press the power button on i here it try and start up and i hear the fan then nothing, one other thing that might be worth noting is this problem started about 2 months after i got a new dvd drive installed as the old one was faulty and as soon as i received the laptop back it was acting weird with pop up bubbles saying stuff i didnt understand, just wondering if anyone could possibly know what this may be as i would like to have a rough estimate of what it would cost to fix before i take it to a professional as i may not beable to afford to fix it if its a big problem, any ideas would be greatly appreciated thanks...

I would take the machine back to whomever installed your replacement DVD drive and tell them to fix whatever problem they caused.

The issue is likely a broken wire or connection. This can be cheap, if it's just a wire, or very expensive if the connection is part of the mainboard, which would have to be replaced.

Again, this sounds like a problem caused by your last repair-- it should be on them to remedy it.