I built my pc a couple of months ago and was a big dissapointment from the beginning. I bought this pc to be able to play high quality games but whenever i do , it eventually crashes causing a weird image on my screen either; completely orange, grey with black stripes, black screen or pink. It sometimes also causes a "buzzing" sound whenever this happens. The only way to be able to use my pc again is to turn it on and off by the power switch. At first i thought it was overheating so i got 4 new fans. My pc never gets hotter than 55 degrees while playing the high quality games. Overheating was not the problem. Then i thought it was my power supply because it was extremely cheap and came with the case. Now i have one of the best power supplies voted by the community. Turns out that was not the problem either. All drivers i can find is up to date and i don't know where to go from here.
My specs are
Motherboard: ASRock Z77M mATX
HDD: 500GB Western Digital Caviar blue, SATA 600 16MB, 7200RPM
Processor: Intel Core i5 3570K 3,4 Ghz
RAM: Corsair 8GB CL 10 1600MHz VENGEANCE
Graphics card: Gigabyte HD7850 2GB
Power Supply: Seasonic X-Series 850W 80 plus gold
The multicolored display may be your monitor not supporting the image your graphics card is sending. It may well be that your graphics card just doesn't cut it as well. Change the resolution of the games you are running and check for improvement. Make sure connection between the monitor and PC are, well, connected. And check for driver updates for your graphics card. Finally, check your BIOS settings for a video buffer size. My BIOS allows either 1 MB or 8 MB and they make a huge difference in video quality.