Hi I am running ubuntu 13.10 on a DN2820FYKH. I have installed intel graphics updater for linux to make sure everything is up to date and have also updated the BIOS. After I wake the computer from suspend on ubuntu there is no hdmi signal so my screen is black. I know the computer has awoken as I can hear it and see it on the network as well as my plex media server which runs on the system works.
There is no picture though, I have to reboot the computer from the power button for the picture to come back.