I'm playing this GOG game (Tzar: Burden of the Crown) on a Windows 7 computer. Whenever I'm playing the game, these weird purple and green lines will randomly appear on the screen for a few seconds. They won't go away unless I do a level screen scroll (it's a RTS game where the level is a huge map, and I use the arrow keys to scroll the map). Here's the craziest part. I tried to take a screenshot of what I am seeing, yet the purple and green bars didn't appear in the screenshot!
Also, this only happens with GOG games. It does NOT happen with the other modern games I have installed on my computer (GTA V, Far Cry 3, The Sims 3, KSP, etc.). So is there some sort of setting in my graphics card control panel that will help stop this from happening? Thanks!
Windows 7 Ultimate (x64 bit)
Intel Core i7
16 GB RAM
Dual Display Adapters: Intel HD Graphics (3000), and NVidia GeForce GT 555M