I get a black screen when I boot my laptop.

The laptop was in sleep mode initially, so when I pressed the power button, it looked as if it woke up from sleep mode, but the screen was blank. So, I held down the power button to force shutdown the laptop and then removed the battery. But after booting the laptop the screen still remains black. The bios/boot screen remains black as well.

I have tried connecting it to external hdmi/vga/s-video devices and booting still no go.

Windows loads fine, as I can type the password and get the 'Ding', then alt-f4 and shutdown windows.

If it helps, the laptop model is Asus G1S-A1.

Thanks in advance!