Display Problem

Allright, I am not so good at technology as I use it just for my Study. I have got Windows 7 with RAM 1 GB and Hard disk 160 GB installed. I also have a TV tuner card (external). This is the problem I have been facing for past a couple of month that is driving me crazy.
Whenever I open the computer, the CPU works perfectly,but the display isnot shown in the monitor though the CPU is running perfectly. When I turn off the CPU directly, then also this problem persist for some time. After turning off the CPU directly for 3-4 times, the display is shown in the monitor and it works perfectly. To my amazement, although I have shut down the PC directly, by pulling off the plugs, the windows doesnot shows me any warnings of turning off the PC directly. The display is perfect when using TV card.
What might be my problem and how possibly on Earth can I solve it?

The issue looks like with your monitor. As your system is working fine then there are two possibilities. First that your monitor is not properly working because of which you are not getting display. Second the cable which is attached behind the monitor to the CPU is not working. Try to change that. That is a fast and easy way. If still there is no display on the monitor then just test your system on a different monitor. Do not regularly shut down your computer directly many times as that can damage your ram and processor.

How are u gonna explain this After turning off the CPU directly for 3-4 times, the display is shown in the monitor and it works perfectly. To my amazement, although I have shut down the PC directly, by pulling off the plugs, the windows doesnot shows me any warnings of turning off the PC directly

When you use Windows XP and if this thing happens then you get Scan Disk on the boot time. This is a blue screen which thinks that due to some issue with the hard drive your Windows has crashed while in Windows 7 you will not notice such issue. There are no such indication on the screen. But this can really damage your CPU, RAM and Hard drive. Sudden Power down can destroy small chips on the motherboard.