Displayport/HDMI quirks

[comptrh]

Hi,

 

I was wondering if anyone else here has any quirks like this one and any decent workarounds.

 

We have recently purchased Dell Optiplex 3020's and a bunch of Promethean ActivPanels to go with them.

Now the Dells have Displayport and no HDMI so I have had to purchase a cable that is Displayport to HDMI, which is what the

the ActivPanel uses.

 

The Desktop monitors are connected via VGA and this is cloned to the ActivPanel (so the kids can see the teachers desktop).

 

Now all works fine accept when booting up, the ActivPanel is not detected (I need to check first if the Panel needs to be on before powering on the Desktop though, I'll update if this works or not) when you turn the panel on it will display no signal and right clicking and going to the Intel context menu to see if you can set the desktop to Clone, it does not off the option "Output to:", that is, until you unplug the displayport/HDMI cable and replug it, then voila, the panel is instantly picked up and all is hunky dory until the next day!

 

Any thoughts would be great. Cheers for any help.

[Gongalong]

It may or may not be related, but there are issues with our Promethean ActivPanel displays on HDMI ports 1 and 2. Apparently Promethean use a faster newer chipset on these ports, and it has caused compatibility issues. HDMI ports 3 and 4 use a slower older chipset which can have better compatibility. In this case though the laptop doesn't even work on ports 1 and 2.

 

Our AV supplier raised this with Promethean after lots of testing at another school and Promethean are investigating, but they're using HDMI 3/4 as a workaround for now. We seem to be encountering the same issue with a couple of laptops, and I'm just about to test here if moving ports solves the issue.