The GeForce GTX 480 is the flagship model for Nvidia’s new DirectX 11 capable 400 series. Before we talk about all the new features and abilities of the GTX 400 series, lets compare the GTX 480's specifications to the GTX 280.
The only area in which the GTX 480 has improved is the memory bus type, the texture unit count (and as a result the texture fill rate) and the max power draw. The GTX 480 was probably not limited by its texture fillrate which means that those transistors were put to better use instead of being wasted. In terms of memory, the addition of GDDR5 balances out the lower memory bus width.
The GTX 480 is capable of all the tradional Nvidia antialaising modes plus a few new ones. In in the control panel where supersampling was the selectable option for antialaising transparency there are now options for 2X, 4X and 8X transparency supersampling antialaising. Under antialiasing setting there is a new 32X CSAA option as well.
The most basic additions to DirectX 11 are as follows:
• HDR Texture Compression
• Multi-threaded Rendering
• DirectCompute 11 - Physics and AI
• Shader Model 5.0
• Hardware Tessellation
The bottom four features on that list are the most important to PC gamers so I will briefly touch on each of them. Multi-threaded rendering is all about increasing the efficiency of the graphics processor by sending data through many pipes (or tubes!) instead of just a few. The idea here is the prevent shaders and instructions from being queued. Just like people, data does not like to wait in line.
The gaming uses for DirectCompute 11 include shadow rendering, artificial intelligence, physics, and limited amounts of Ray Tracing. Outside of gaming this feature can be used for video playback and transcoding and stream computing. Click here for more information from Nvidia on DirectCompute.
Shader Model 5.0 makes shader coding much easier for game developers and allows us to enjoy shadows that are larger and look more realistic. This article at Tom's Hardware has an easy to understand example of how it makes life easier for code monkeys.
Hardware tessellation is all about giving more detail to 3D objects in real time, without your frame rate taking a nose dive. Rocks, trees, hair, people and even water can all look much more real when tessellation is applied. For more information you can check out our Unigine Benchmark results and you can watch the water and hair demo videos located here.
3D Vision Surround
This is not exclusive to the GTX 400 series, but it is launching at the same time as the GTX 480. 3D Vision Surround requires two GTX 260 or better GeForce video cards (or a single GTX 295), three 120Hz monitors and three dual link DVI cables. At Nvidia's PAX East booth I witnessed Battlefield Bad Company 2 running on three LCDs and Need For Speed Shift running on three projectors. The projector solution looked very nice because there is no bezel to get in the way, however the projector setup in that booth would be very difficult to install into a room in your home. 3D Vision looks really cool on an extended monitor setup, but at this juncture I am not sure if it is worth the $600 it would cost to get two more 120Hz monitors.