I've been using my new PC build for a couple of days now without any issues. I was having GPU issues a few days ago, but those have been since been resolved and up until now I've had no issues.
Now, all of a sudden, I'm having issues with white lines flickering on my monitor. These lines only seem to appear and flicker when I'm viewing a video (on Twitch or YouTube for example). They also only appear inside the video window itself. An example of what I'm talking about can be seen here: The last thing I was doing before this issue occurred was re-downloading and adding album art to my iTunes library. I also installed f.lux about an hour before the issue occurred. I disabled f.lux to see if the problem went away, but it didn't. I'm not sure if uninstalling f.lux and restarting would help or not. Other than that, I haven't done anything that I can think of that would have caused an issue like this to occur.
Also, white lines appear on other web pages, not just pages that contain Flash/video content. These lines do not flicker, they just appear on web pages and remain stationary. An example of this issue can be seen here:
Other details: The monitor I'm using is connected via DVI. I also have an cheap, simple Dell VGA monitor connected for multitasking. This issue occurs on the VGA monitor as well. The VGA monitor is connected to the motherboard and the DVI monitor is connected to the video card. I haven't played any games on my PC yet, so I'm not sure if this issue occurs in-game. I had the refresh rate set to 144Hz, and decreased it to 60Hz when the problem started occurring; this did not help. My PC specs are listed below:
Monitor: Asus VG248QE 144Hz 24.0" Monitor
GPU: Sapphire Radeon HD 7970 3GB Video Card
CPU: Intel Core i5-4670K 3.4GHz Processor (currently not overclocked)
CPU Cooler: Corsair H100i
Motherboard: Gigabyte GA-Z87X-UD3H ATX LGA1150 Motherboard
Memory: 2x4GB Patriot Viper 3 DDR3-1600
SSD: SanDisk Extreme 120GB 2.5" SSD
HDD: WD Caviar Blue 1TB 3.5" 7200RPM HDD
OS: Windows 8 (64-bit)
PSU: Cooler Master Silent Pro M 700W 80 PLUS Bronze
Case: NZXT Phantom 410