The monitor in my computer turns dark when i turn the laptop on

This sounds like a bad display on the laptop. Hook up an external monitor to the vga port on the laptop. You may need to toggle the display to output to the external monitor. This is generally accomplished by pressing the "FN" key + one of the F# keys. Look for an icon that resembles a monitor or it may say LCD. If the graphics display correctly on the external monitor, then you will need to replace the computer screen.

Sounds like either there is a bad connection from the computer to the monitor, or the monitor has a faulty power regulator, causing the monitor to overheat prematurely, and shut off.

Does the fault appear on the laptop screen aswell? It appears by your description that the fault is only on the external monitor. If the screen comes on for a moment and then goes blank as described, then this appears to be an invertor fault. It is very common among laptop and tft screens and requires the invertor inside the panel to be replaced / repaired. Simply plug the screen into another computer to confirm.

Have you tested it with an external monitor?

I would say you either have a damaged inverter board or screen baclight lamp. Usually the inverter board fails in one of the following ways:

1. When you turn on the laptop, the screen lights up for a short period of time and then goes dark. You still can see an image but it is very dark, almost invisible and definitely not usable. When you restart the laptop, the screen lights up and then goes dark again. The laptop works fine with an external monitor.
2. Your laptop turns on but the screen remains dark all the time. You still can see a very dim image outline. The laptop works fine with an external monitor.
3. The laptop screen works fine for hours or even days, but sometimes it goes very dark as it mentioned above. When you restart the laptop, the screen works fine again.

Inverter failure symptoms are very similar to backlight lamp failure symptoms and in most cases you cannot tell which one is causing the problem until you replace either the inverter board or the backlight lamp. From my personal experience, inverter boards fail more often than backlight lamps. If you have to guess, replace the inverter first.

1.)It could be your video card
2.) Yes it is expensive for a laptop
3.)I would first check your screen setting for turning off display...

If you are using vista:

-Right click on your desktop then choose personalize
-Then click screensaver
-On bottom click on "change power settings..."
- On the left click on "choose when to turn off the display"

Your monitor can turn off without your computer being in sleep mode.

Your laptop's monitor went bad and needs to be replaced. I had the same problem on an IBM laptop I had. Replacing the monitor costs between $120-220.

The make and model do not matter. Your backlight is going and will have to be replaced. A good computer shop will be able to do it.

may be your power saving option have small time .
check in control panel power option check power shemes.set it to 20 minutes.

It's sort of a solution, but I work in a computer shop and got this screen in yesterday. I looked at it closely and it's actually the backlight that died. I pulled it apart and found that three of the 820uF/20V capacitors had swollen up. If you replace them then you should be fine, but I went for a different approach and took the inverter board from a laptop and put the in the screen and used an external power supply. It's a bit dark but it works fine now.

does the fan work ok? and do you have a laptop holder for it or you just have it on a desk ....get a laptop holder for it if you do not have one and as for the rest goto the power mangment area on the computer and see if the monitor might be on stand by after a few min ...