AMD A-Series Llano APU Sabine Notebook Platform Review
Product Position and Graphics Engine
AMD Llano APU Product Positioning
Now that we have an overview of the architecture of the AMD Llano APU let's look at the specifics of the product position and where AMD sees this APU going in the market.
The AMD E-series is the currently available Bobcat-based APUs for netbooks and nettops while the new Llano parts are going to be known as the AMD A-series. The A8, A6 and A4 series will compete against Intel's Core i7, i5 and i3 line of processors and they will surely be better; after all they are '1' higher right?
In reality these competing lines will match up pretty much head to head in terms of pricing and target markets. We'll have more details on the specific models being launched in the AMD A-series on the following page when we get into the review sample we got from AMD for this article
Along with the A-series launches a new marketing and branding campaign from AMD around the Vision name and some simplified messaging. The cooler logos are seen at the bottom here where you see mention of "dual graphics" which is really a return of the idea of Hybrid CrossFire.
Dual Graphics allows a vendor to add in a discrete AMD graphics solution to a notebook and get increased performance by using the power of the Llano integrated graphics as well. In fact, AMD is actually giving the combinations completely unique model numbers. The graphics portion of the Llano A8 processors is going to be marketed as the Radeon HD 6620G. If you also have a Radeon HD 6770M discrete GPU in your notebook the combined product is the Radeon HD 6775G2. The A8 6620G paired with a Radeon HD 6630M GPU will be a Radeon HD 6690G2.
Yes, I know this is incredibly confusing and likely won't be very useful for our crowed so don't attempt to memorize it; I know I'm not. The goal here is obviously to be able to create an easy to grasp model numbering system that can be presented at stores like Best Buy to consumers that only understand the "higher is better" PC buying mentality.
This dual graphics capability will result in increased gaming and graphics performance across the board though the amount of scaling you'll see will depend on the discrete GPU and integrated GPU combination to a large degree. In the above slide AMD paired an A8 Llano APU with a Radeon HD 6570 discrete desktop card and saw somewhere around 30-35% better gaming performance in a handful of applications over the Core i5 based system using the same discrete card.
These are high end gaming settings or resolutions and thus won't really appeal to the gamer reading this but for a budget system, or in particular for a mobile machine with light gaming capability, dual graphics could be a nice upsell.
The Llano Graphics Engine
We have looked at the x86 CPU core portion of the AMD A-series Llano APU now let's take a look at the GPU portion and see what architecture AMD has implemented. Based on the Redwood GPU design from the Evergreen generation (think Radeon HD 5600), the Llano APU possess a lot of GPU horsepower for an integrated solution.
Each line in the A-series will have its own iteration of GPU specifications with the A8 obviously taking the lead. With 400 stream processors (now being called Radeon Cores) built on 5 SIMD arrays of 80 each, 20 texture units, 2 ROPs and a 444 MHz clock speed, the top option is capable of 355 GFLOPS of raw computing power. The A6 offering drops to 4 SIMD arrays and the A4 has 3 arrays. Obviously we expect performance to scale down with the decreasing shader count in the standard way though I am curious how much the memory data rates of only 1.6 Gbps or 1.333 Gbps will modify the scale.
If you have read any of our AMD GPU stories in the last 18 months the chances are good this diagram will be very familiar representing the "Sumo" architecture found in the Llano core. The update to the Redwood core includes the newer UVD3 engine, additional power gating support for better energy efficiency as well as being integrated to the new memory interface required for being slapped on an APU. Also interesting? This is the first GPU to be built on GlobalFoundries new 32nm process technology.
With the Radeon heritage users that pick up a system based on the AMD A-series of APUs will get many added benefits like this one: much better aniso filtering when compared to the CPU/GPU competition from Intel (on the left). If you don't know the significance of this diagram just know that the condensed, uniform appearance on the right will result in better image quality in gaming. I think this is a trend that cannot be easily overlooked - the graphics drivers from AMD have been and will continue to considerably outpace Intel's in terms of features and performance.
There was at least one interesting addition to the control panel suite this time around, a feature called AMD Steady Video. Using a heterogeneous computing model AMD's driver will have the ability to stabilize "bouncy" video that is usually associated with consumer cameras and unsteady hands. We were just getting a chance to play with this option before we had to finish up this review so expect more on this later.
AMD will definitely be pushing the benefits of the Llano A-series APU to users and OEMs both in standalone configurations as well as dual-graphics systems.
Obviously another big factor for AMD with Llano and the A-series of APUs is DirectX 11 support. Here you can see a very blunt demonstration of that fact as we see not only huge performance benefits with the A-series APU over the Intel Core i5 Sandy Bridge system but also that Intel's processor graphics simply can't run DX11 applications. Many of you will simply shrug this off saying that you can games with at least similar image qualities on the DX9 code path but DX11 offers much more than that including multi-threading support, tessellation support and Shader Model 5.0 support.
One area where the GPU combatants used to thrive is in the world of transcoding applications. First there were CUDA-accelerated transcoding programs, then NVIDIA and AMD supported ones and finally we are getting into OpenCL development down the same road. This slide uses software from Arcsoft to demonstrate the performance advantages seen on the AMD Fusion A-series of APUs where the red bar represents CPU-only transcoding and the green bar shows the advantages when enabling GPU acceleration. Using the DX11-class GPU on the A-series parts you get some very noticeable performance boosts as well as much lower CPU utilization during that transcoding time.
The problem of course with this argument now is that Intel has addressed the transcoding problem on Sandy Bridge with some dedicated logic on the chip, not using the shaders on the GPU. It turns out this results in a much faster transcoding application than even those accelerated by discrete or integrated GPUs from AMD or NVIDIA. The GPU-based designs used on AMD's APUs are definitely more flexible and extensible than the hardwired unit on Sandy Bridge, but we need to see some more software fall into our hands that really utilizes the GPU. Maybe the AMD Fusion Developer Summit will do just that...