egandt here,
I tried using my Ankar 2 Amp charger and encountered similar issues, but not exactly the same, in this case while I could not use the utility to monitor, however I did see that the Nvidia control panel (when the signal was over 300MHz), would flicker every few seconds detecting and then dropping the Vertex (named Samsung) this is likely what was causing the issues previously when HTPC mode was not selected as if HTPC mode was selected the monitor remained present, but nothing was passed through same as previously.
I'm happy to send it back now or if you think that a possible firmware firm is forthcoming that I should try, waiting to try it, as well; you let me know. Suggestion, not sure if it is possible to report how much voltage the Vertex is using if it is that would be a good item to include in the Utility, as it might help with trouble shooting.
Figured I'd PM you on this, and thanks for all your help,
ERIC