Toshiba Laptop - Screen Black - Not Booting Up

Hi,

I would appreciate any advice you could give me.

My Toshiba L850 laptop doesn't seem to be booting up, I am not a 'computer guy' so will describe what has happened and what I have tried - will also say that laptop was knocked off the bed a couple of weeks ago, went blank - off, I pushed power and it restarted and seemed ok and was for two weeks.

A few days ago my daughter was playing a game and said that something was wrong with the computer, when I looked it was blue lines covering the screen and from memory was maze like (not just either vertical or horizontal). I couldnt exit out so restarted it and got met with a blank screen.

Tried a few more times with same result, googled the problem and came across this site an others recommending the hold the power button down trick, plugging in external monitor etc.

Tried these and wasn't having any luck - nothing showing on external monitor and tried the power button hold numerous times, then after really thinking that it was dead the screen did actually show some backlight - still black - after it stayed like that I restarted again a couple of times and eventually got to the toshiba logo - then restarting few times I got to windows login etc.

After windows loaded I saw pinkish lines come across the screen - maze like again and then they turned to blue - restarted again and it was black again and after more attempts havn't been able to get it back.

When I power it on - I hear the disc drive start and the fan comes on but it doesnt seem to then boot the OS. Lights all come on but the 'loading noise' doesnt come and the screen doesnt light up.

I tried checking that the hard drive and the RAM was in properly - first time looking at that stuff.

I am hoping that the fact it did actually come to life again once means it's not a goner and maybe something I could fix myself or cheaply with a computer shop.

Thanks for any advice