Mac is showing weird Pixels & Bars..?

hey people,

have problem 2 days , when busy doing stuff on mac in while happens lot of strange weird looking things come in screen :s

here example of mean -> here
, here

weird things on screen?!
, @ finder it's going crazy!
, it's driving me crazy kind of virus or need reinstall thing xd
tired repair disk mac cd , said no problems!

please

 

create new account , see if issues exists too. graphical glitch

 

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