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I have a MacBook Pro Core Duo 2.4GHz (MB470xx/A) with OS X 10.6.4 (Snow Leopard). I am trying to add a second 1920x1080 display. (Currently one display using the native DVI-D out is working just fine.)

Going back in tech a few years I resorted to buying a Villagetronics VTBook PC Card. This card has DVI-D out and supports 1920x1080 resolution (its a 32MB Trident video card). I am using a Rosewill ExpressCard to CardBus Adapter to slot the VTBook in.

When hooking up the card I get the message:

Because a USB device was drawing too much power from your computer, one or more of your USB devices have been disabled.disabled.

After a short while both the PC Card and the ExpressCard adapter get very hot to the touch.

At no time am I able to configure a second monitor.

I have installed the Villagetronics OS X drivers for the card and I have tried both hot swapping and inserting the card with the MacBook Pro turned off (the requirement for getting this device to work under Tiger on PowerBook models).

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And could someone please tag this vtbook as well please? I cannot, <200 rep. – cfeduke Nov 10 '10 at 5:37
This sounds like a hardware problem. The VTBook probably requires more power than the Macbook Pro can provide. Similar to those 2.5in HDDs with the USB cables with two connectors to draw power from two USBs, without the workaround. – Daniel Beck Nov 10 '10 at 22:40
Maybe there are ExpressCard/PCCard adapters that have an additional power connector? – Daniel Beck Nov 11 '10 at 13:17

@Beck is right... It sounds like the MacBook Pro is not giving the USB video adapter enough power. Try hooking up a powered USB hub, and connect the video adapter to that hub. If that doesn't work, then the USB video adapter is probably defective. (Just make sure to remember to plug in the power for the powered USB hub)

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There actually is no USB interface here, its a PCMCIA (PC Card) connected to an ExpressCard/34 adapter going into the ExpressCard port on the side of the MacBook Pro. – cfeduke Nov 11 '10 at 2:06
@cfeduke I'm pretty sure ExpressCard is connected via internal USB, see the last post here. This explains the error message wording. I suspect PC Card allows more power to be drawn than the MBP ExpressCard provides, so even with your adapter, you're out of luck. – Daniel Beck Nov 11 '10 at 13:15
It's not USB (at least not externally, where he could do as you suggested). – Daniel Beck Nov 11 '10 at 13:17

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