Operating System Factors and Workarounds
Unfortunately, there are problems associated with using the ExpressCard interface to drive an external graphics card, and these problems are not transparent to the user. First, let’s consider the operating system.
The WDDM graphics architecture used in Windows Vista will only allow one graphics driver to be running at a time. This forces the user to match the version of the ViDock they purchase to their existing integrated video chipset: that is to say, if your laptop has an integrated Radeon video chipset, you need to purchase the Radeon version of the ViDock. If your laptop has an integrated Geforce video chipset, you need the Geforce version of the ViDock. If your laptop has an integrated Intel video chipset, you’re plain out of luck; no version of the ViDock will work specifically for these chipsets.
Village Tronic mentioned that while it is theoretically possible to force a Radeon or GeForce version of the ViDock to work on an Intel chipset by installing the XPDM driver model, this would disable features like the Windows Aero interface, DirectX 10 graphic fidelity, and hot-plugging. More importantly, Village Tronic won’t guarantee it will work at this time, as XPDM driver support isn’t what they’d like it to be.
On the plus side, Vista does allow for hot plugging, and system bus resource allocation will not be a problem in this OS. All monitors driven by both the ViDock and the internal graphics adapter will also allow the Aero interface to be enabled.
As an alternative, we’ll consider Windows XP: unlike Vista, XP supports multiple graphics drivers, so the type of integrated video chipset used doesn’t matter. While this situation is ideal, it turns out that some laptop manufacturers don’t follow PCMCIA configuration/booting procedures as strictly as they could in their BIOS, and as a result some laptops simply won’t recognize the ViDock. While Village Tronic claims to be working with manufacturers to update their BIOSes, it’s probably a good idea to check their compatibility list before committing to purchase a ViDock for a Windows XP machine. For example, the Windows XP laptop in our lab was unable to work with the ViDock (see Installation and Issues, below).
Macintosh operating systems OS X Tiger and Leopard are also supported with the specific ViDock Gfx Mac Edition, which can handle all of the advanced 3D capabilities of OS X. The only drawback is that hot plugging is not yet supported.
