AMD unveils Radeon HD 8000M GCN family
December 18, 2012 // 10:30 a.m.
AMD has officially unveiled its Radeon HD 8000M family of graphics processors, after being embarrasingly pipped to the post by the unveiling of an Asus Ultrabook with at-the-time unannounced Radeon HD 8550M dedicated graphics.
The first in the company's 8000-series of mobile graphics processors, the family is split into four ranges: the 8500M series takes aim at the budget market that has outgrown integrated graphics, while the 8600M and 8700M offer progressively improved performance before the whole range peaks with the 8800M for high-end gaming. If you're paying attention, you may have noticed something interesting: there's no 8900M series, the 28nm Graphics Core Next (GCN) equivalent to the current top-end mobile enthusiast chip series the Radeon HD 7900M. That's something AMD is clearly aware of, leaving a clear gap at the top and bottom of its Q2 2013 roadmap for 8400M and 8900M products.
Ignoring unannounced future products, let's take a look at what AMD has actually unveiled. The entry-level Radeon HD 8500M series features 384 stream processors and an engine clock of up to 650MHz depending on precise model. The memory clock is up to 1,125MHz on models with GDDR5 or 1,000MHz on models with cheaper DDR3 memory, and the chip manages a claimed single-precision compute of 537 gigaflops or 33 gigaflops in double-precision mode.
Moving up the range, the Radeon HD 8600M series includes the same 384 stream processors and 1,125MHz/1,000MHz memory clock but running at a higher engine speed of up to 775MHz. Accordingly, there's a boost to performance: single-precision compute goes up to 633 gigaflops and double-precision to 39 gigaflops. The story is the same for the Radeon HD 8700M: 384 stream processors, up to 1,125MHz/1,000MHz memory clock and an engine clock running at between 650MHz and 850MHz depending on model. That in and of itself is an interesting choice: at its bottom-end 650MHz configuration, the Radeon HD 8700M series is identical in performance to its cheaper Radeon HD 8500M; it's only when the clock is upped to 850MHz that improved compute of 691 gigaflops in single-precision and 42 gigaflops in double-precision becomes available.
Finally, there's the Radeon HD 8800M, AMD's flagship mobile GPU - at least, until the Radeon HD 8900M inevitably launches next year. Unlike its stablemates, which vary only in performance, the Radeon HD 8800M is a very different piece of silicon: the chip boasts 640 stream processors to all other 8000M-series' 384. There's also no option for DDR3 memory, with manufacturers being forced to fit faster GDDR5 running at 1,125MHz if they want to fit the GPU to their products. The result is a beast of a mobile GPU: at its peak speed of 700MHz, 150MHz slower than the Radeon HD 8700M, the extra stream processors make themselves felt with 992 gigaflops of single-precision and 62 gigaflops of double-precision compute power.
The decision to limit the engine speed of the Radeon HD 8800M to below that of the Radeon HD 8700M provides a clue, too, as to AMD's plans for the range: next year's Radeon HD 8900M will, in all likelihood, be an uprated Radeon HD 8800M running at the full 850MHz.
What AMD hasn't yet shared are details of the chips' in-game performance and thermal design profile (TDP) figures. The official launch slide deck does provide a chart demonstrating a claimed performance increase of between 20 and 70 per cent in popular games including Battlefield 3, Crysis 2 and Skyrim compared to Nvidia's GeForce 650M mobile GPU, but without providing actual framerates.
Pricing information on the parts, which - as you would expect from laptop-targeted parts - are available only to OEMs, has not been provided.