This could be due to a lot of things, but none of which involve your RAM. It could be:
1)Line Noise, 2) Insufficient or corrupted power supply, 3) Bad graphics adapter, 4) Failing monitor, 5) Elecetrical disturbance (from a device, such as speakers around your monitor), 6) Strong magnetism from a nearby source, and many other things. Complete the steps in this order to find out whats wrong -
1 - Make sure all connections for the monitor are properly connected.
2 - If you have spare monitor adapters and cords, try using them.
3 - Plug the power cord of the monitor into a different outlet running off a different circuit in your home.
4 - Try moving any electrical devices near your monitor at least 8 feet away.
5 - Try using a certified, grounded extension cord for your monitor
6 - If none of this makes a difference, if you have a spare monitor try it.
7 - Make sure the GPU of your system isn't dusty and the fans are working.
8 - Try lowering the refresh rate of your monitor to 70-75 and setting the resolution as high as it can go, restart the computer.
9 - If all this fails, it still may not be a problem with your PC as a whole, but bad electricity in your home. If you live near a switching grid, or some other high power station then this is a common problem in homes after heavy lightning storms. Your system will get shocked (surge protector or not) due to bad wiring and create corruption in the flow of electricity to your PC.
Try starting the PC up normally and once booted, abruptly hit the retstart button. On the first screen shown as the computer reboots abruptly hit the power button (not restart), and quickly hit the power button again to start the computer up. This isn't a permenant solution and isn't good for your pc health if done a lot, but it solves the problem temporarily.