Original URL: http://www.theregister.co.uk/2007/12/20/amd_mobile_roadmap/

AMD lays down laptop platform plan

Mobile roadmap 2008-2009

By Tony Smith

Posted in Hardware, 20th December 2007 11:22 GMT

What's AMD got planned for notebook makers and buyers over the next few years? Its plans are broadly known - the 'Puma' platform will be released in 2008 followed by the first 'Fusion' architecture mobile CPUs the following year - but now we can begin to flesh it out a little.

Puma incorporates 'Griffin', AMD's first mobile processor designed as such from the ground up. That said, the 65nm dual-core part will incorporate processing cores taken from the Turion X2 family, each connected to 1MB of L2 cache for 2MB in total.

AMD's work on the CPU has focused on improving the northbridge elements: in comes HyperTransport 3 with the addition of bus-power management circuitry to clock it up and down dynamically according to need.

AMD's 'Griffin' notebook processor

Inside AMD's Griffin

Griffin's dual-channel DDR 2-oriented memory controller features a pre-fetcher to grab ahead of time the data it thinks the processing cores are going to want from memory in the near future. It's also tweaked to work only with notebook-style memory configurations and not the broad array of desktop and server memory options the current Turion line is architected to be able to deal with, albeit unnecessarily.

These northbridge components and the two cores are all on separate voltage planes, allowing each to run on reduced power when they're not needed. That allows, for example, a chipset-integrated graphics engine to connect through to main memory without troubling the CPU cores. The cores themselves are able to switch frequencies independently and quickly - in microseconds rather than milliseconds - with the ability to fall to a lower base frequency than Turions - they fall to 800MHz, while Griffin will go down to 300MHz.

Puma's second key component is the 'RS780M' chipset, which will come to market as the M780. This is a mobile version of the 'RS780' desktop chipset - aka the 780G. Both will contain a DirectX 10.1-compatible graphics core and support PCI Express 2 for the addition of discrete GPUs - such as AMD's upcoming next-gen 'M8x' series, expected to appear in the form of the M82, M86 and M88, targeting budget, mainstream and peformance-oriented systems, respectively.

The chipsets will support on-the-fly switching between integrated and, where present, discrete GPU(s). It's also thought that users will be able to accelerate 3D graphics using both graphics cores, CrossFire fashion.

The M780 will connect to AMD's SB700 southbridge I/O chip, which has ports for 12 USB 2.0 devices, two USB 1.1 add-ons, six SATA drives, parallel ATA and PCI add-ons. It also has the usual power management and HD audio support, and can incorporate a Flash module on the ATA bus.

Come 2009, AMD will introduce the SB700's successor - 'SB800'? - and incorporate it into 'Shrike', the follow-up to Puma. Shrike's key element is 'Swift', a 45nm mobile processor based on AMD's third-generation 'stars' processor core. That seems to separate it out from what AMD calls the 'Falcon' family of Fusion-architecture products, which are based on a CPU core known as 'Bulldozer'. Swift is due in the second half of the year.

Swift will be AMD's first CPU with an integrated GPU - the next component to come off the northbridge and onto the processor die now it's already shifted over the memory controller. The memory handler will be upgraded to support DDR 3 memory. All these changes will require the introduction of a new interconnect.

AMD's 'Falcon' Fusion processor design

AMD's 'Falcon' processor design for 'Fusion' CPUs

Swift is expected to provide PCI Express lanes and control circuitry for discrete graphics chips - such as the mobile 'M9x' series due to be launched in 2009.

Fine details about the 2009 products are scarce, but we can expect Swift to enhance Griffin's power saving technologies and - thanks to that 45nm fabrication process - sport more on-board cache, including a shared L3.

Finally, there's 'Bobcat', AMD's processing core for UMPCs and mobile internet devices. The feline codename might seem to align it to Puma, but since it too is a ground-up design, the codename probably indicates a design heritage rather than a direct relation.

Given the kind of handheld devices Bobcat-based processors are being designed, it's not hard to imagine Bobcat cores being dropped on dies alongside a GPU - a key characteristic of the Fusion design.

Bobcat has been said by AMD to consume just a single Watt of power - though that's a design aim, and may not be delivered by first-generation Bobcat CPUs.