My screen below the taskbar keeps on flickering

that sounds like a either a monitor issue or video card issue. in most cases, if it is a video card, you wouldn't see the image on the screen. I would try the monitor, if you had it for quite a while, it is possible that the monitor is going bad.

I know it is not software problem.

Hi nvashum,

Here's what you need to do. First just to see a little more of this flickering, right click on the MS symbol or start button, then click on properties. When the window pops up, go to task-bar and click on the button that says auto-hide task bar, then click ok. Once you've done this, it will shrink the task bar down below so you can see if the flickering happens to be some program or it's still along the bottom of the screen. If that shows you nothing, then you can reset it back if you'd like. OH! to get the task bar to pop up again, just move your cursor down to the bottom of the screen and it will pop up for you.

Now, if you find nothing unusual or obvious with that first attempt, the next step would be to find a friend with a monitor that you can hook your computer up to. (P.S. Take your monitor with you as well.)
Turn it on and see if you get the same results. My bet is no, but who knows! Then take your monitor and hook it up to your friends computer to see what results you get. If it does flicker then guess what? It's your monitor for sure.

Now, if it doesn't flicker, then it still could be your video card or on board adapter. Most people don't have extra video cards lying around, so, what you do is go HERE and get some direct advice about the monitor and video card. Plus you can also see if it's still under warranty. Most of the time, these things are as simple as adjusting the settings on the monitor. But they built it, they would be the best ones to manage the hardware issue.

The only other thing I would recommend is to download the driver for it to make sure that it's current. HERE.

Hopefully one of these suggestions will fix your flicker.

Good Luck

Mark