I have a second monitor (touchscreen) to add to a laptop (Win 7 64). Video is fed with HDMI, USB for the touch, and 12VDC for power. It works perfect when plugged directly to the laptop.
But I need the screen about 13 feet from the laptop, so I need (?) to use a USB extension cable. Then the touch does not work.
I tried active and passive 5 meter cables.
A passive 4 foot cable does work.

Tried the monitor on another laptop(Win 7 64), and same results: does not work.
Tried on a Win 8 pro laptop, still no go.

Tried the touchscreen monitor on a desktop PC(Win 7 64): works fine. Add in the active USB extension cable, and still works fine. It loads as a HMI device, using standard Microsoft drivers (does not need drivers from the monitor mfg).

I have disabled the power management of the USB ports, and even taken apart the active cable to test for 5VDC, it is there on the far end of the active cable. When it fails on a laptop I get unknown device in the USB family tree in device manager.

Since it works on a PC, but not laptop I have to assume something is configured differently on a laptop USB, but I'm no "superuser". I'm just a guy who needs to add a second monitor and have the dang touch work. Any help is very much appreciated.

  • 1
    This would be easier to read if you could break it up into paragraphs instead of one huge wall of text. – JakeGould Sep 14 '15 at 1:34
  • Since the setup seems to work with a desktop PC, that would seem to rule out USB timing issues. So then the likely culprit is power. Would be interesting to get measurements with an in-line device such as this: banggood.com/… – sawdust Sep 14 '15 at 1:48
  • Jake thank you for breaking up to smaller bites, I don't post much on forums and did not realize my ramblings were so long. – Chris Dahl Sep 14 '15 at 15:20
  • Sawdust, I did take the small plastic shroud off the active USB cable and measure 5.1-5.2 VDC at the far end of the cable when connected to the laptops, and all three laptops tested were plugged into wall power so power management of the USB ports should not have been an issue, though I manually took power management off on all three to be sure. – Chris Dahl Sep 14 '15 at 15:23
  • I have one of the USB test devices mentioned by Sawdust coming today, will update with findings.... – Chris Dahl Sep 15 '15 at 14:42

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