The root port on your PC supplies 500 mA. If you plug a 4-port unpowered hub into it, the hub itself uses 100mA, leaving 100mA for each device port, assuming you're actually going to fill all 4 ports. But if you're only plugging in say 2 devices, one that uses 100mA, the other (an iGesture or TouchStream) still has 300mA (plenty) available, and things can work fine.
Except that Windows applies a very conservative power policy, asking each device how much peak power it can use (not directly sensing the power usage). If any device reports a peak usage > 100mA, Windows disables that device unless the hub has external power. Why? Because Microsoft is afraid you'll fill all 4 ports with > 100mA devices, none of the devices will work and you'll have no idea why!
Linux, and possibly Mac OS X, don't bother to apply this conservative power policy, which is why Magic can get by OK with his two devices on the Linux hub.
MrLightTouch wrote:Kensington manufactures the original keyboard that the iGesture keyboards were built from.
Because the builtin Kensington USB hub is weak, you can't upgrade firmware when the NumPad is plugged in thru that hub. You need to unplug the short iGesture NumPad cable and plug it directly into your PCs root hub or another externally powered hub. Depending on your desk setup, you might need to get a USB extension cable for this.
& First Zero-Force Typer
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