RIP? https://gfycat.com/UntidyAnimatedBumblebee edit: Apparantly it goes away when I disable my secondary. Still means something failed I guess. Apparantly this is the 150mhz memory dual screen bug, I installed 1.7.2.1 and it seems to be fine, for now.
If your video cables are fine your memory or even core diode has solder ball issues under the mpga chip. You can send me a pm with your dumped gpuz bios .rom and we can mod it so it won't happen again or even prevent it all together... Or Pull the beast, dismantle the cooling and all vrm pads/ etc... wrap the whole thing up in like 6 wraps of tin foil... use a razor to cut a square where the core diode is... heat oven to 375f possibly? (450f for old nvidia) make 4 tin foil balls on cookie sheet.. place gpu on foil balls core facing up. Then heat for 15min (when complete/ let sit and cool in the oven/ do not touch it for another 20min)... this time and temp are up in the air though on AMD... though the extra tin foil wraps prevent damage to caps. Then it should be working perfectly... Though a bios mod is highly advised to correct all the issues you are having. Must know the clock it is running at and temperature at which point the lines appear on any/ all displays?