iMac is freezing and picture is pixelized
I have this iMac that freezes after a couple of minutes of operation; the mouse completely freeze and thera are color pixels everywhere random on the screen.
I have teared the system down and changed the thermal paste on the graphic card (nVidia GT130 512Mb), the CPU and the chipset as well.
The system has been cleaned from dust and I've re-imaged the hard drive with a new version of El Captain OS-X.
Can it be a faulty Video Card?