Console versions of Mass Effect 3 have an option (Extras --> Settings --> Online) to disable the connection to EA servers. Is there a way I can do this on my Windows 8.1 PC? I already have the game patched to not need Origin open (yes, I bought the game and DLC legally, I just hate having Origin open in the background), but can I prevent the EA server connection?
The problem I think you might run into is that the game needs to check with the servers to prove that you did indeed buy the game and its DLC, and it needs to do this every friggin time you hit any main menu. I know it drives me nuts, since it's not exactly the quickest and it does it so often.
This question was kind of explored in this thread, and the consensus seems to be that you can maybe work around the EA link, but it's a hassle (assuming it even works). I have not personally tried it, choosing instead to just curse EA and its anti-piracy efforts every time I'm stuck waiting for it to verify things it's verified a thousand times before.
So, short answer: The game needs to verify you bought what you bought every time you touch it, and will only let itself be played (or at least, let its DLC be played) if it can connect to the EA mothership. This means that no, you can't prevent the server connection. If there is indeed a way to fool the game that won't get one's account banned, I'd be interested to hear it.