After a lot of confusion and frustration, I finally realized that this issue was caused seemingly not by twitch or flash player itself, but from two specific twitch streams:
www.twitch.tv/C9Sneaky and /incarnati0n
I don't know if it's relevant but these two are currently streaming from South Korea.
Basically whenever I watch either of these two streams, after a seemingly random period of time the video feed will heavily artifact and a moment afterword my video driver will crash repeatedly for about 30 seconds until finally recovering (almost) completely. I reboot when this happens though 'cause I've noticed some things don't seem to work quite the same afterword.
It's the strangest thing. I haven't yet found anyone else's twitch stream that causes my display driver to crash like this.
I've tried updating/reinstalling Flash and Shockwave, I've tried disabling hardware acceleration in flash, I've tried using IE (I primarily use Firefox), and so far none of these have shown any difference. What I did do however, is run a Debian virtual machine and watched the stream through that (also in Firefox) and didn't have any issues.
Other things I've tried have been reinstalling and updating all AMD CCC drivers and software. (I was previously on the original Omega driver release while having this issue - still having the issue on 15.8 Beta)
I've also upgraded from Windows 8.1 Pro x64 to the Windows 10 equivalent - still the same issue.
My primary and secondary monitors run at 144hz and 60hz respectively, but I've set them both to 60hz to test and there was no change in the issue.
I tried searching the forums but I didn't seem to find anything quite like this, so I apologize if there is and I didn't find it.
I will post my system specifications in detail, and if there is any more information that could help I will be more than happy to provide it.
Thank you all in advance,
AMD R9 280X
AMD HD7970 GHz Edition
(Neither cards are overclocked - they are slightly underclocked, to 1000MHz GPU and 1500MHz base Memory speeds. This is to match the speeds that Flash forces the cards to operate under.)
AMD Catalyst Driver Version, and Driver History:
Catalyst Version 15.8 Beta
Previously the original Omega driver release, I forget the exact version number.
Windows 10 Professional 64-bit [fully updated]
Previously tested, Windows 8.1 Professional 64-bit [fully updated]
AMD FX 6300 Six core processor at 3.5GHz
Overclocked by multiplier to 4.5GHz
(I have tested this issue without overclocking in place.)
Display Devices and Connections Used:
Primary: Asus VG248QE - Mini Displayport to Displayport
Secondary: Asus MS228H - DVI to HDMI
Motherboard BIOS Version:
System Memory Type and Amount:
G.Skill Sniper Series DDR3 1600 4GB Chip *4 ~ 16GB total system memory
Corsair RM1000 (1000 Watts)
All hard drives are standard, WD Black Edition drives. (two 500GB, one 1TB drive)
I have about six total case fans of varying sizes - the important thing to mention is my temperatures never break 50C on any component.
I have no optical drives or additional expansion cards installed.
I have run both Windows chkdsk and DISM commands to make sure my system is in healthy condition. I've also run a virus scan using the ClamAV engine.
I have also done extensive stress testing to ensure complete system stability, both at stock speeds and under current overclock.