Sudden problems with my game; I can't deduce what's causing it.

I play WoW on my Mac with Windows Bootcamp. After some initial trouble with certain addons my game has been running smoothly for 6 months.
I went away for a few months and now my game is having problems.

Firstly, I keep getting disconnected, but only at certain times. It seems to be when the server has a lot of users, and if so, usually when I'm in Dalaran. My game is LargeAddressAware and I can push the game over 2GB of RAM usage, so don't think that's the problem. Like I said, it never used to crash before. I've spent a lot of time trying to fix the game and not playing so I'm still learning when it happens. One time I got disconnected after 2 hours of playing and I was just flying around Storm Peaks. Other times it repeatedly disconnects me as soon as I log in (again usually in Dalaran or ICC). I keep trying to log in, and usually I then have around 2000ms latency and keep rubber-banding all over the place before getting disconnected repeated again. Oddly, it can suddenly magically be fine again for a few hours.

Secondly, my game has started doing weird things with the graphics. Here are some screenshots: https://imgur.com/a/MaMTwts

It only does this occasionally, and will persist until I change the camera angle. If I keep flying the problem will go away because the camera angle changes. I've not managed to capture a screenshot but occasionally it looks like this screenshot that someone else posted about: https://imgur.com/a/huADhVQ (unfortunately there was no responses to their thread). When I've had the black objects they weren't circular like in the screenshot but more like planes that could cover most of the screen.

The patterns and strange objects that are drawn depend on what else is on the screen. They move at the same rate the mobs do (flapping wings etc.) , or will change when a mob moves to a particular position.

I switched internet provider and have a new router which means the disconnects could also be because of that. I have a good enough spec mac and internet speeds for WoW; and like I said, it worked before perfectly fine.

I've re-downloaded the game client and moved the data to a new part of my hard drive. I also booted Windows to a USB and the disconnect persisted. I have also downloaded the HD client and again get disconnected (whenever I'm also getting disconnected from the main client; because as I've said, it often works fine for hours with no problems).


If anyone can tell me what's likely to cause the graphics issues, that would be great. I assume it's either the data being loaded in wrong, but I don't really know. I've played around with all the system video settings and nothing changes it. I also found a thread which says to run this:

/console gxcolorbits 24
/console gxdepthbits 24
/console gxrestart

but it didn't help. I've played with 'hardware cursor' and it doesn't fix it.

Any suggestions what I can try? Any help would be greatly appreciated.