Take the 2-minute tour ×
Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

I'm trying to connect my laptop (Dell XPS 17 L702X) to a TV via HDMI. In the process I've hot-plugged the cable several times, but to no avail. Could this damage the HDMI port on my laptop or TV?

share|improve this question
    
When in doubt, a good hint is taking a look at the connector. If some pins protrude others, those are most likely ground pins, that have to be connected first, when hot plugging. SATA, USB, etc, they all work this way. –  polemon Jun 24 '12 at 16:12
add comment

5 Answers 5

up vote 10 down vote accepted

According to the HDMI specification, yes it's hot-pluggable.

It supports "HPD" (Hot Plug Detect Signal).

The HPD (Hot-Plug-Detect) feature is a communication mechanism between a source and a sink device that makes the source device aware that it has been connected/disconnected to/from the sink device. When an HDMI cable is inserted between the two devices, the resulting hot-plug detection instantiates a start-up communication sequence.

share|improve this answer
add comment

HDMI, like most modern cable interfaces, was designed to support hotplugging. The HDMI connector uses pin 19 as "Hot plug detect".

share|improve this answer
add comment

Yes, all the monitor Port is hot plugged. I've plug and unplugged to my HDMI thousands times and there is no problem.

share|improve this answer
add comment

As noted in the other answers, it's hot-plug, as per the specification.

Damage may be physical, or electrical.

Physically, type A connectors should be good for over 10,000 insertions (as good as micro-USB).

Since it's possible to get imperfect (simultaneous) mating of all pins, one side may not initialise correctly during hot-plugging, that ought not cause damage. HDMI is robust against shorting any combination of pins.

Warnings that come with HDMI devices or cables instructing you to power-off before connecting may be intended to minimise electrical discharges and other effects due to potential differences between grounds (the cause of "ground loops").

In my experience, aside from old or bad wiring, the main sources of ground loops are cables originating from different providers: cable, phone and electricity. Ethernet with metalized RJ45 connectors could also cause problems.

It may be prudent to interconnect devices with different input sources while the devices are powered off, but still plugged in so that they are grounded.

So to answer your question: if your TV has a direct connection to an analogue coax cable provider, there might be a ground loop which could in principle cause damage to circuitry when making connections. If your laptop is not plugged in to a charger this is less likely to occur.

One additional consideration might arise due to HDCP (content protection) -- when you have more than two HDMI-capable devices the order in which you plug things in may cause different end results. Whether that conflicts with your understanding of hot-pluggable is up to you ;-)

share|improve this answer
add comment

We repair televisions that have had their HDMI IC's damaged by 'Hot Plugging'. Either the software has been corrupted, or the actual IC damaged, causing the HDMI input not to work. It seems to be a risk as the plug/sockets wear. Best not to take a risk, and switch off before inserting.

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.