From what I see your answers are downvoted because you do not supply information enough to actually fix the issue, you link to other sites without explaining why it would be a solution for the problem.
Example for comparison:
Tells the user what the problem is (his card is not supported anymore), links to the site that shows where I got the conclusion from and explains what are the next steps (even without specifying then written) to take.
Tells thee user "oh, there is much information in the interwebs, I found this site with solutions that might or not work for you, you need to have a look at them and see if it fits.
The rest of your answer downvotes are about speculative situations (ie: Ubuntu Edge) and probably would be better deleted and the question flagged as off-topic for the site since any answer will be good enough, but not 100% correct since we do not have enough information...
You should also refrain from accusing people from downvoting, votes are part of the site, if a users targets your user and starts downvoting things randomly then the system will tell us (opposite is also true), and remember 1 downvote = -2, 1 upvote = 10, if your asnwers are good the votes will balance themselves mostly without interaction and intervention, I would not worry about one downvote.