Currently we finished the updates for windows 7 in two computers. In this two computers (A normal desktop and a better desktop), the updates of IE 11 is what really matters. This update brings a lot of changes in WebGL rendering results in all versions (especially for versions after 37) and new fonts in firefox versions 44 to 53.
The main differences are anti-aliasing. But for version 37, the update of IE 11 introduces some bugs for model renderring (make the results darker). I dont know the reason. Maybe we need to break down the update of IE 11 and check the details.
Actually we found that windows 8 has the same condition with windows 7. IE 11 brings a lot differences.