I don't think this is a pc or mac issue. This is a perception issue. Most pc users are probably coming from AutoCad which has a real time scroll zoom without any annoying pausing bitmaps. We can try all kinds of settings and upgrade to the fastest equipment, but it is still not going to fix the scroll zooming issue. My suggestion would be for Nemetschek tech people to actually try the AutoCad scroll zoom to realize what posters are referring to. Maybe then, Nemetschek can realize and fix the problem. By looking at the posts, this is a very persistent and real problem. I hope this gets fixed soon in a patch or next version of Vectorworks.
Thanks,
seaprt