I didn't spend a lot of time looking into it, but my guess in my case is the new aspect ratios are closer to some standard size and it's easier for the vidcard to push the video. This is strictly a guess and it'll probably be something completely different.

I'm glad it did turn out that way... I had to buy a new vidcard to get the 3 accounts to run, and was crying on the inside (like a kung fu man) thinking I was going to have to get another vidcard to run 4 accts.