Screen turns fractal?

Recently bought an ASUS S400CA-RSI5T about 4 months ago. After a month it acquired a problem of the screen turning fractal. The first time it happened I was installing RAM. Wanted to see if the computer was reading the RAM (which it still doesn't read?). So I snapped the case of the laptop on, but didn't put the screws back in the case, and turned on the computer. With the computer in hand, I was turning down the volume on a Harman/Kardon AVR 240 audio receiver for the TV. I touched the volume knob of the audio receiver, and the screen went fractal and made horrible noise. The screen did it again a couple weeks later, which again involved being around the audio receiver. Next, it started to happen more frequently not involving the audio receiver. It seemed to involve the computer getting too hot, but now the fractal was not as chaotic as at first and the noises stopped. So I started using a fan, and then it seemed to involve slightly bumping the computer. Now today it happened without bumping it, while using a fan. The computer will not do anything but shutdown once fractal. When shut down and rebooted, seems to work fine. I've had a couple of instances where this wasn't the case. It's probably happened 50 times total now. Here is a picture of the screen. http://tinypic.com/r/i6jj3k/8