Fujitsu Seimens this week announced its external laptop graphics solution will launch later this month. The device is a relatively straightforward implementation of a new platform for external GPUs and other PCIe devices on laptops that was unveiled by AMD this summer. While the current device isn't that compelling—it's appearing on only one laptop so far—it does play Crysis, and the technology behind it has a great deal of promise.

Mobile graphics chips are generally not suitable for high-end gaming or some professional work. Even the laptops marketed for gaming or as workstation replacements carry high price tags and fall far short of desktop parts, performance-wise, as the power consumption and heat of more capable parts simply can't be reconciled with increasingly compact laptop chassis constructions. Battery life also suffers with the higher-end mobile parts.

The new Macbooks and Macbook Pros exemplify one approach to solving this problem. They pack two NVIDIA GPUs, a lower performance, lower heat, lower power chip for mobile use, and a higher performance, higher heat, higher power chip for use when needed and while on wall power. This approach, while it helps, still leaves notebooks using notebook parts, and doesn't allow any upgrading.

Last year, AMD decided to solve the problem by putting the GPU outside the laptop in a breakout box. This has been done before, in various ways, but AMD wanted to build a standardized system that would make graphics cards as swappable for laptops as they are for desktops. The bus required for this system was a serious concern. Although it's barely possible to run low framerate, low resolution graphics over a USB 2.0 bus, USB is obviously unsuited for general graphics applications. ExpressCard offers a close facsimile of PCIe in an external format, and some external graphics solutions, like the ASUS XG Station, have used it. AMD's internal testing, however, showed that, for gaming and video applications, the single PCIe lane offered by ExpressCard was simply inadequate to allow desktop-like graphics performance. A new interface was needed.

AMD's solution was simple: they brought PCIe outside the case, pin for pin. Sunnyvale contracted with JAE for a connector which could handle PCIe bandwidth at low cost, while remaining small enough to fit on thin laptop cases. The cable will run a short distance from a connector on the laptop to a similar connector on a breakout box, where the exact same circuitry as an internal card can perform the exact same function. In theory, there should be no performance difference between XGP systems and the same GPU in a desktop graphics card implementation. The XGP connector allows up to eight lanes of PCIe 2.0, and a larger x16 connector is in the planning stages.

This physical connector is dead easy for any laptop vendor to build into their laptops, and dead easy to design external devices for, as the circuitry is the same as PCIe. Nothing fundamental prevents it from being used on Intel or VIA laptops, or with NVIDIA GPUs, or even other PCIe devices. New drivers shouldn't even be needed. AMD, however, has done more than enable these devices. When the platform was announced in June, AMD also announced new drivers for their Radeon GPUs that would allow them to drive the laptop's internal screen with the external GPU on systems designed for such a feat. Further, they've provided reference designs for a few possible uses of the new platform, including single and dual GPU external graphics cards.

The current design closely tracks AMD's intended use of the technology. Fujitsu Seimens has built an XGP-compatible breakout box containing a Radeon HD3870 mobile GPU and offering HDMI and DVI ports. This box, dubbed the AMILO Graphic Booster, is to be released as a package with Fujitsu Seimens' upcoming Amilo 3650 laptop. The AMILO laptop will be a fairly standard puma design with a Turion X2 Ultra ZM-86 processor in a 13" chassis and the standard dressings, including a Radeon 3200 integrated GPU.

The real selling point will be the Graphic booster, which purports to allow desktop-style PC gaming, rendered either on the laptop's screen or an external monitor. With two external monitors on the Graphic Booster and one on the laptop's own GPU, the expansion bay will allow a total of four monitors to be used. A pair of USB ports allow a keyboard and mouse to be connected to the expander. The package will cost about $1650, Fudzilla reported in August, and will launch later this month, Fujitsu Seimens announced this week.

If AMD's vision comes to fruition, laptops could one day switch graphics cards more easily than desktops, allowing painless upgradability and a sort of super docking station through an XGP port, turning the laptop into a real desktop equivalent at its home base. The laptop's CPU could consume a larger portion of the thermal budget when onboard parts like the GPU aren't in use, allowing faster CPU performance.

But the external PCIe bus raises the possibility of options well beyond gaming. Extra hard disks, sound cards, speakers, monitors, printers, and other peripherals, could all be connected to the XGP breakout box, or embedded in it. In fact, future boxes could allow desktop graphics and other PCIe cards to be plugged in, giving the user freedom to choose his own external GPU or upgrade it freely. Rendering boxes could be open loan equipment in offices. Of course, some of these options might take up as much space as a regular desktop.

Those of us looking forward to our younger relatives asking if they can borrow our graphics cards will have to wait, though. While the long-term potential of this idea is quite striking, its current implementation gets you a relatively anemic GPU at a high price, with a lock-in to a single model of laptop. Over the next few years, though, it's likely this idea will provide far more options, and bring interchangeable graphics cards and other expansion products to the laptop world.

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