Hi I am Tech Michael, I have read all the conversations you and the other tech Russell have posted and have had these issues myself.
On this particular one there is a key sequence that needs to be entered to get this TV to connect as a monitor.
Unfortunately I don't remember the sequence lol, but I know its very do-able;-)
I have used both Linux and Windows with the same working results on this TV.
You can try calling Samsung support on this for that info which they should have available to you, but also I have put in a tech request for this info as well. it may take me a day or so to get that depending on when they are able to reply to me.
In any case, I will stick with you until this is complete.
Please rate kindly thus far, it won't cost you anything to rate my service to you kindly,
Then you can reach me by simply replying to this message anytime.
Thank you and have a wonderful day!
You can reach the correct site for this: 1-***-***-****.or (1-800-SAMSUNG)