Here's an overview of the new features in Catalyst 10.3:
ATI Eyefinity Technology Bezel Correction - compensate for your bezels so objects in your game move from one display to the other smoothly ATI Catalyst Mobility - monthly updates for the mobile crowd ATI Eyefinity Technology Per Display Control - adjust for differences in each individual displays brightness, color and contrast ATI Eyefinity Technology Multiple Display Groups - more display groups to give further control of your desktop with three displays or more connected ATI Eyefinity Technology Display Configuration Switching - easily switch from one display mode to another 3D Stereoscopic 3D driver hooks - enables 3rd party middleware vendors to bring more 3D stereoscopic gaming optionsHere's a list of performance enhancements you can expect from Catalyst 10.3a:
Aliens vs. Predator
* Overall performance increases 5% on ATI Radeon HD 5000 Series products
Battleforge
* Improves up to 8% on ATI Radeon HD 5000 Series products
* Improves up to 3% on ATI Radeon HD 4800 Series products
Call of Duty: World at War
* Improves up to 2% on ATI Radeon HD 5000 Series products
* Improves up to 6% on ATI Radeon HD 4800 Series products
Company of Heroes
* Improves up to 6% on ATI Radeon HD 5000 Series products
* Improves up to 3% on ATI Radeon HD 4800 Series products
Crysis and Crysis Warhead
* Improves up to 6% on ATI Radeon HD 5000 Series products
* Improves up to 2% on ATI Radeon HD 4800 Series products
DiRT 2
* Improves up to 30% on ATI Radeon HD 5970 graphics products
* Improves up to 20% on ATI Radeon HD 5800 Series and ATI Radeon HD 5700 Series products
* Improves up to 10% on ATI Radeon HD 4800 Series products
Far Cry 2
* Improves up to 6% on ATI Radeon HD 5000 Series products
* Improves up to 4% on ATI Radeon HD 4800 Series products
Left 4 Dead & Left 4 Dead 2
* Improves up to 3% on ATI Radeon HD 4800 Series products
S.T.A.L.K.E.R. Clear Sky
* Improves up to 2% with ATI Radeon HD 5970 graphics products
* Improves up to 2% on ATI Radeon HD 5800 Series products
Resident Evil 5
* Improves up to 5% on ATI Radeon HD 5000 Series products
* Improves up to 3% on ATI Radeon HD 4800 Series products
Tom Clancys H.A.W.X.
* Improves up to 15% with ATI Radeon HD 5970 graphics products
* Improves up to 20% on ATI Radeon HD 5800 Series products and ATI Radeon HD 5700 Series products
* Improves up to 3% on ATI Radeon HD 4800 Series products
World in Conflict
* Improves up to 5% on ATI Radeon HD 5800 Series products
* Improves up to 3% on ATI Radeon HD 5700 Series products
* Improves up to 5% on ATI Radeon HD 4800 Series products
Note: This list is not exhaustive and more improvements are possible