AMD just published the Catalyst 15.3 beta driver, you can download it over here for Windows 7 and 8.1.
This is the release you need to enable FreeSync support, at present it only works on single-GPU configurations but next month the firm should have a driver ready that adds FreeSync support for CrossFire. Other than that, the Catalyst 15.3 Beta adds Mixed Rotation Eyefinity as well as a bunch of new and updated CrossFire profiles and some bug fixes.
Highlights of AMD Catalyst™ 15.3 Beta Windows Driver:
AMD Freesync™ Support for single GPU product configurations
AMD Freesync technology support is now available for single GPU configurations. For more information on how Freesync works, FAQ's and what products are currently supported, please visit the Freesync Technology Page
Mixed Rotation Eyefinity now available on Radeon™ R9 285 series
AMD Radeon™ R9 285 now supports Mixed Rotation Eyefinity for "0" and "90" degrees rotations
More information on setup, configuration and support for this feature is available at the following link.
New Crossfire Profiles for:
Far Cry 4
Lords of the Fallen
Total War: Attila
Crossfire Profile Updates for :
Assassin's Creed Unity
Civilization - Beyond Earth
Ryse: Son of Rome
 Screens may blank out when enabling a 3x1 SLS with 3 HDMI monitors
 Leadwerks : Project Manager crashes with a "Pure Virtual Function Call" error
 Second Life : Rigged mesh objects are not rendered correctly when hardware skinning is enabled in the in game settings
 Star Trek Online : Block corruption is experienced when MSAA is enabled in the in game settings
 System hangs/BSOD upon resuming from S3/S4 sleep on AMD Radeon™ R9 285 configured in AMD CrossFire™ mode
 With AMD CrossFire™ enabled, Timeout Detection Recovery (TDR) occurs during actual gameplay when YouTube Mix moves to the next song in Firefox
 Screen tearing on enabling VSync with Alien: Isolation game
 Catalyst Control Center Video Quality settings may not be available or retained if the "Enforce Smooth Video Playback" option is not selected on some AMD HD series GPU's.
 Primary display may not be retained after disabling Crossfire while in Eyefinity mode
 Enabling or disabling Crossfire may lead to one side of the 4K MST display being shown as black
 Minor stuttering may be seen in Dragon Age Inquisition on Single and Multi GPU configurations?
 Total War : Attilla - The game may hang during in game cinematics on certain Kaveri platforms with a separate discrete GPU
 The Elder Scrolls V - Skyrim : Fog / Clouds may flicker on Radeon HD 5800 series products