Vertical lines on my toshiba tecra s2 screen

I have a problem with my toshiba tecra s2. When i turn it on nothing appears on the screen unless i press on the video card or vga. And even then only vertical lines will appear on the screen. So i connected it with an external monitor and again nothing appears unless i press the video card or vga. But this time the the BIOS screen appears perfectly with no vertical lines. However, it ends there nothing happens unless i press the vga again and when i do i get some error messages. I connected it with a brand new laptop screen and it gave me the same vertical lines no BIOS screen. I had to press again before i even get the lines. I dont know what the problem is. I need some help