Hello,
I've run into the same problem with the SIIG USB to VGA converter which touted Windows 7 compatibility. Aero is enabled for my primary monitors (since I have a high end graphics card) until the converter is plugged into a USB port, and then Aero features such as tab preview, transparency and peek are disabled. I am using the USB to VGA converter for a third monitor for which I do not need high graphics quality. However, Windows 7 automatically disables these Aero features when it detects hardware that isn't compliant with it's own internal requirements and hoses Aero for all monitors. I am sure that any USB to VGA converter, as they stand now, are not compliant and Aero will be disabled. I've found another company, Lindy, that sells a similar converter to the SIIG and their software package is completely compatible with my converter. I looked at the Startech product and it uses identical software as well. This suggests to me that the chipsets are the same and the state of the drivers for these devices is not advanced enough to comply with Windows 7 Aero requirements, but do indeed function nicely otherwise with Windows 7. There is a black hole called WDDM (Windows Display Driver Model) that I believe graphics card software driver designers must adhere to in order to function seamlessly with W7, but that is not currently being supported by the USB to VGA converter software driver designers yet.
Having said that I am on a quest to determine if I can manually fool Windows into enabling Aero even though I don't have compliant hardware. There are various registry hacks that I've found, but they don't work. I believe this is the only path open to us right now.
Take a look at the info in this link:
http://www.webtlk.com/2009/01/24/how-to-turn-on-windows-7-aero-theme/
You might try the registry hack, perhaps you can get that to work. If so I'd like to know.
Best regards,
Blake
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