Im having strange blue dot - line when i watch movie or play game

Is that a new build or you changed the graphic card?
What is the Wattage of your PSU?
What does the "blue lines" look like? Are they thick?

I would like to have more info about this problem.  

i have been using this graphic card for about 6 months
psu - 355 W it seems my psu doesnt have the specs labeled but the model no had 355 so im guessing thats the wattage.

ill rephrase blue line, its more like blue dots lined in horizontal. length is always different since it appears and disappears randomly but mostly about half of the sreen. and its not thick mayb about the size of the basic form of line in ms office.

thank you

There is no way that you can run a HD 58xx on a 355w PSU... Try to remove your PSU from your Computer Case, the label should be there. (It is on every PSU)

If it is really a 355w PSU, it may be an underwattage problem. Else, it would be the Graphic Card dying.

Try to use HWMonitor and check the temps and voltage when you play games.

Hope it helps!  

i just checked the back of my PSU

it says its 600W. sorry for the wrong information

so it seems my graphic card is dying  

Did you try your graphic card on a other computer?

Did you try HWMonitor to check the temps and voltage?

I only got 1 desktop at my home

http://imageshack.us/photo/my-images/24/volt.png/

this is the result of HWmonitor i ran while the game is running on background

All seems normal to me.

If you ever tried uninstalling your GPU driver and run on onboard GPU and the problem persist, we can conclude its your monitor being flawed.

If not, your GPU is having something we PC gamer called an artifact, which is essentially a defect of that said GPU's graphic processing that created an anomaly on the screen regardless whatever that is. And artifacts cannot be fixed. The cause for this are vary from a flaw product to damage caused by overclocking. You can google to confirm this, since I'm just too lazy to gives you for case examples  

Yeah I second that. Update your driver. Check your cable isn't missing any pins or anything.

Also, if you've ever overclocked your GPU, there is a chance you may have fried it.