Why won't my external monitor not detected?

December 1, 2014 8:17 AM

I bought a new laptop, which doesn't have VGA input so i bought a new cable ( HDMI Gold Male To VGA HD-15 Male 15Pin Adapter Cable 6FT 1.8M 1080P ) To connect my external monitor to my laptop. I connect the cord, it fits in snugly on both ends, but no external monitor is detected. Do I need drivers? or some kind of convertor? Thanks. (FYI my monitor is a dell 2001fp, and my laptop is a dell DELL XPS 15 9530 )
posted by crawltopslow to Computers & Internet (13 answers total)

Some laptops require a key combination to enable mirroring. Not sure why, but look for a F-key with a vaguely "external monitor" looking icon and try fn+that key, with the monitor connected.
posted by Alterscape at 8:19 AM on December 1, 2014

Response by poster: My F8 Key is a extermal monitor key, it brought up some options.. it seems to detect an external monitor as #2, and I clicked "extend" and now my clock isn't on my task bar on my laptop ( i assume it's being 'displayed' on the external monitor, but the external monitor is all black, even when i switch it from DVI-D to S-video to Composite to D-Sub) (by the way which one of those should be correct?
posted by crawltopslow at 8:24 AM on December 1, 2014

D-Sub would be the correct one [See here].
posted by jangie at 8:27 AM on December 1, 2014

Response by poster: If it helps any, nothing happens when I unplug or plug the external monitor cord in.
posted by crawltopslow at 8:27 AM on December 1, 2014

Response by poster: When it's on D-SUB, it just displays "self test feature check" with the words red green blue white moving across the screen. It seems the laptop doesn't realize there is a monitor connected as far as i can tell.
posted by crawltopslow at 8:30 AM on December 1, 2014

Response by poster: Oh, according to the product: "note: Not all of devices with HDMI or VGA interface is able to use this cable.
Analog signal and digital signal are hard to transfer, so please check your devices carefully before you place order.
Please note that it doesn't work with laptops to LCD monitor directly and that you will need an adapter box to convert the VGA signals to HDMI in the first place.only our cable is not enough."


So should I get an adapter? or just get a new cable? my laptop has hdmi only, the monitor ports are several options (including the white one called DVI-D i think
posted by crawltopslow at 8:38 AM on December 1, 2014

I don't think you can do what you what you want with a simple cable. You're trying to connect a HDMI output on your laptop to a VGA input on the monitor, correct? This can't be done with a "dumb" cable, you need something "active" to convert the signal differences, i.e. the adapter.
posted by achrise at 8:40 AM on December 1, 2014

Way cheaper to go HDMI-DVI-D, it's a digital-digital connection, no conversion needed
posted by Oktober at 8:41 AM on December 1, 2014

Response by poster: Awesome, I'll get an HDMI DVID cable on ebay, they seem to be under 5 bucks
posted by crawltopslow at 8:42 AM on December 1, 2014

Just to throw this out there because I've made this error more than once: did you double check to make sure that the monitor itself is still selected for the right display type? There is usually a button that allows you to cycle through the various input possibilities for the monitor, and I've sometimes bumped the button resulting in a nice black screen until I figure out what happened.
posted by SpacemanStix at 9:10 AM on December 1, 2014

Response by poster: yeah, i scrolled through every input type. thanks. this time it was that the cord doesn't convert digital/analog
posted by crawltopslow at 9:15 AM on December 1, 2014 [1 favorite]

Please note that it doesn't work with laptops to LCD monitor directly and that you will need an adapter box to convert the VGA signals to HDMI in the first place.only our cable is not enough."

That makes it sound like the cable you bought is trying to convert VGA output to HDMI input... which is the opposite of what you want to do. So, maybe the wrong gadget to start with.

Unless you have a really nice monitor, probably more practical to buy a new monitor that supports native HDMI input. Monitors are cheap and you're going to spend $50 just making this conversion work otherwise.
posted by qxntpqbbbqxl at 9:57 AM on December 1, 2014

Typically cables like this which appear to go from a digital source to analog destination (HDMI to VGA in your case) without any digital-to-analog conversion hardware only work if the computer itself is set up to output an analog signal over the digital port. Unless the manufacturer sells a cable like this for your specific model of computer, I wouldn't expect it to work, and even then it might only work with the manufacturer's cable rather than a third-party cable.

The HDMI to DVI-D cable already suggested should work for your scenario, since HDMI is compatible with the DVI-D spec.
posted by Aleyn at 4:05 PM on December 1, 2014