AMD A10-5800K Preview: Trinity for the Desktop



Product: AMD A10-5800 APU, Asus A85X Pro Mainboard
Company: AMD
Author: James Prior
Editor: Charles Oliver
Date: September 27th, 2012

Feature Overview

Trinity brings old and new to the table, with VLIW4 graphics as seen in 2010's AMD Radeon HD 6900 series and the GPGPU compute options that offered - but also a brand new, never before seen CPU microarchitecture: Piledriver. Piledriver is the second iteration of the new CPU microarchitecture AMD launched in 2011, known as the Bulldozer family. The first Bulldozer family appeared in Opteron and FX processors, with a new method of improving core density known as modules. Bulldozer family CPUs are built out of modules, with each module containing a shared front end for two x86 integer cores and a fancy floating point unit (FPU), a design AMD marketed as Clusterbased Multithreading (CMT). CMT offers up to 80% of the performance of the same two threads running on full, single, BD cores, but at much lower power. Trinity also gains the first unified northbridge on the die, and PCIe replaces HyperTransport for connecting to I/O devices.

Trinity Die

Manufactured on the same 32nm process as Llano (and the Bulldozer-based Zambezi) and using the same 100W TDP, the new Trinity APU is claimed to offer 37% more general PC performance and 25% more graphics performance. The die increases in size slightly, 246mm2 to Llano's 228mm2, with transistor count increasing from 1.178Bn to 1.3Bn. The CPU core count claim remains the same, four, with the GPU core count changing from 400 VLIW5 units to 384 VLIW4 cores. The branding goes up, the top dog quad core Trinity is an A10-5800 with Radeon HD 7660D graphics.

APU Evolution

With the Radeon HD 7000 series, AMD launched 3 chips into six products for the retail consumer. The Southern Islands series use AMD's brand new Graphics Core Next (GCN) architecture, and can be found in the AMD Radeon HD 7700, 7800 and 7900 series of cards as well as various FirePros. If you're an OEM or system builder, however, you can buy AMD Radeon HD 7300, 7400, 7500, 7600 graphics cards to sell in your prebuilt PC. These OEM only cards are rebranded versions of the Radeon HD 5400, 6400, 6500 and 6600 series of cards. So where does that leave Dual Graphics, the feature that allowed the first gen APU to offer mainstream discrete gaming performance by adding a single GPU to an APU?

Trinity Graphics

The AMD A10-5800 supports Dual Graphics, using the same AMD Radeon HD 6500 and 6600 series of graphics cards; the internal HD 7600D designation of the APU graphics doesn't break compatibility. Alongside this expansion capability is the built in turbo core, boosting individual cores and the GPU to higher clock speeds as workload demands change. The TDP balance now swings both ways, unlike Llano where it was fixed in favor of the GPU permanently, now the unlocked K-series can push up higher without throttling other parts unnecessarily.

AMD Powergating

The memory controller speeds and channel supported are unchanged, dual channel 1866MHz and quad channel 1600MHz by default. 1866MHz support is through AMD's AMP, AMD Memory Profile technology, leveraging the same technology as Intel's XMP to offer JEDEC default timings and speeds out of the box and simply select higher performance, perhaps non-standard speeds, timings and voltages without having to validate the settings yourself. That's not the only trick the memory controller has, as it can drop speeds when bandwidth requirements are low and only use a single channel to refresh a static screen. The high performance memory configuration selected at boot doesn't have to be the only configuration during use, non-bandwidth hungry operations can be spared full out memory performance and power cost. Thanks to the improved memory controller features and new IOMMU, the GPU shaders can operate directly in x86 virtual memory, the GPU can be virtualized, and the CPU can access dedicated GPU framebuffer.

GPU Compute Capabilities

The video playback capabilities are enhanced too, with the new UVD and VCE features seen in high end Radeon 7000 series cards present to offer hardware H.264 encoding, dual stream HD + HD picture decode, and MPEG-4 / DiVX decode hardware acceleration. Accompanying this is positional audio, allowing up to four independent 7.1 channel streams, matching the number of audio capable attached displays. This audio can be content protected high bitrate, too, for BluRay or other media playback.

Bulldozer vs. Piledriver

Our preliminary testing of the A10-5800 with an ASUS A85X Pro mainboard so far shows it to be very good at managing power, with our test system idling at around 30W, 45W to browse the web and play HD video, topping out at 130W for a session of Battlefield 3 at 1920x1080 low settings and an average of 22FPS. Our Intel system featuring a Core i3 2120 and ASUS P8H67 Deluxe can match the idle power at and is surprisingly close at web browsing, HD video playback. Battlefield 3 at 1920x1080 is DirectX 11 on the Sandy Bridge DX10 GPU, bluergh. BF3 runs at 8fps average, an unplayable slideshow with peak FPS matching the A10 5800K's lowest. In gaming performance terms, the A10 5800K is estimated to be similar to the Core i5 3450 with a discrete GPU like an NVIDIA GT 630, a combination that costs a lot more.

AMD Dual Graphics performance scaling

With the AMD A10 APUs expected to be in the price range of an Intel i3, that's a very disruptive play. Consumers look to spend as little as possible to get the job done, typically looking first on price and then on performance. AMD's second generation HSA platform is redefining what is possible at different price points, leveraging the APU graphics to get more done as well as offering more raw power for the traditional graphics workloads. Building a PC for 3D movies, enhanced content Blu-rays, AAA gaming, video & photo editing, accelerated web use, local stored or remote streamed movie playback and more is now a single chip. In our full review we'll test the performance of the CPU and GPU side as well as the new features, and give you our product award. Stay tuned.

AMD A-series APU Preview