I don't remember this being a problem before. I'm running an RX 480 with the latest 16.12.2 drivers (tried 16.12.1 first) and cannot get Fullscreen to stop tearing. I can only stop it by using Borderless Windowed, which suffers a performance hit. Forcing through the control panel has zero effect, and the in-game V-Sync option causes the tearing to appear more uniform, but doesn't stop it.

Any ideas?

System Configuration:
Motherboard: GIGABYTE GA-990FX Gaming
CPU: AMD FX-8370
Memory: 16GB DDR3 @ 2133MHz
GPU: Sapphire Radeon RX 480 8GB NITRO+ OC
VBIOS: 113-2E3470U.x51
Driver: Crimson 16.12.1, 16.12.2
OS: Windows 10 x64 (1511.10586.713)

Steps to Reproduce
1. Install The Witcher 3.
2. Turn all graphics settings to Ultra except Foliage Distance to High.
3. Turn the camera quickly horizontally or vertically.
4. Enable V-Sync in-game and repeat step 3.

Expected Behavior
Enable V-Sync in Fullscreen to stop screen tearing.

Actual Behavior
Enable V-Sync in Fullscreen to alter the behavior but still experience screen tearing. Instead of anywhere it wants to go, it will tear in a solid horizontal line.

If you are experiencing tearing and are using V-Sync, you *must* also enable Triple Buffering in your video control panel. V-Sync will not work without it.

Can't seem to find that in Radeon Crimson Settings. Tried using D3DOverrider as well, no luck. Thoughts?

Can't help you with Crimson I'm afraid. And you're going to have to use D3DOverider if you want VSync and Triple Buffering on The Witcher 3, since it's a DirectX game (Triple Buffering is an OpenGL thing). Try adjusting your screen refresh rate, and try to use the monitor's native resolution and frequency.

I already did that.