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I have an early 2007 Macbook Pro running 10.5 that I've recently set up on a KVM with my primary desktop system.

The problem I've run into is that I have a 20" 1680x1050 LCD, and OS X only provides options to mirror at the resolution of the built-in display or to span. Since the built-in display runs at 1440x900, this leads to running my LCD at non-native res and a fuzzy picture. There isn't any option that I can find to simply disable the built-in display entirely and run the external LCD at its native resolution.

I am aware of closed lid mode, but the MBP was disassembled while in storage for about 6 months (took it apart to pull the HDD) and the cable to the touchpad, which controls the sleep sensor was damaged, meaning closed lid mode won't work. I've looked into replacing the cable, but the cheapest I've been able to find it is $75-100, and I'm trying not to invest any more money into this computer as it also has a completely dead battery and a few other minor problems.

I've found the app SwitchResX which appears to allow you to do what I need, but it has a lot of functionality I don't need and a ~$20 registration charge attached to it.

An odd set of circumstances, I'm aware, but I was hoping somebody might know of an OS hack that would let me just disable the internal display and be done with it. :)

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The easiest fix is in the display arrangement. You can leave the built-in display active, just arrange it so that it's at a corner, and put the menu bar on the external display. You might have to play with the arrangement depending on where you keep the dock. It's a cheap hack, but it sounds like that's what you need(ed).

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This might do the trick for you.

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Unfortunately, what they're discussing doing is activating the sleep sensor by using a magnet since the screen's gone. My problem is that the cable that carries the sleep sensor signal is damaged, so triggering it doesn't do any good. – jslaker Dec 12 '09 at 15:17

I think your solution is going to include kernel modification. I don't know if you are up for the task, but you can try either booting without the following kernel extension:


Or finding a replacement for it from a source like those used by the hackintosh community.

I think I would try working without it at first...

Move the file to a ...kext.back, clear the kernel cache and reboot. If you have any trouble boot with verbose mode (-v) and have a look at the error codes.

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When you span, you should be able to choose the resolutions of the two displays independently. One solution to your problem may be InsomniaX. You can use it to sleep your display.


I've never tried it and the developer recently released a 10.6-compatible version before throwing in the towel. The source code has been released for someone else to take over the project. Luck!

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Spanning doesn't really help since I have the MBP slipped in a space between my desk and desktop so save space. :) Just gave Insomniax a try. Didn't seem to help any. – jslaker Dec 12 '09 at 15:23

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