Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Iv been using my HDMI slot to run a 24" monitor and all was well. I borrowed a 17" monitor from work to run a dual screen set up, plugged it into the d-sub port and nothing happened. Checked the new monitor on a laptop and it worked fine. Next i unplugged my 24" from the HDMI slot and tried that in the D-sub and nothing happened.

Can anyone help?

share|improve this question
what kind of graphics card are you using? onboard, which mainboard? or dedicated, which card exactly? – Baarn Jun 1 '12 at 16:53
It sounds like the d-sub port on the motherboard is broken. – Ramhound Jun 1 '12 at 17:53

Depending on your computer/video-card setup, you might need to manually enable the second display port in your Windows Display Properties

From Windows Support Site:

  1. Open Screen Resolution by clicking the Start button Start orb image, taken from linked MS page, clicking Control Panel, and then, under `Appearance and Personalization**, clicking Adjust screen resolution.

  2. Click the drop-down list next to Multiple displays, click Extend these displays, and then click OK.

    Screenshot of drop-down, taken from linked MS page
    The Multiple displays option appears only when Windows detects more than one monitor connected to your PC.


  • If you don't see an option named Multiple displays in your display settings, then Windows isn't detecting a second monitor plugged into your desktop computer. Or, it is not detecting an external monitor plugged into your laptop. When Windows detects this monitor, it will appear in the drop-down list next to Display. If you don't see it listed there, try clicking Detect.

  • Make sure the monitor you want to extend your desktop to is turned on and plugged into the correct video port on your computer. You might also need to select the correct source labeled on your monitor's controls to ensure the monitor is using the correct video port. For more information, check the manual for your monitor or go to the manufacturer's website.

share|improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .