I'm hoping that someone else has possibly encountered this before so that they understand what I'm describing.
My wife and I just moved to a new place and the movers haven't arrived with our stuff yet; so I've been using an ancient laptop for the past few days. This laptop generally works more or less OK as long as I don't have more than one or two programs running at a time (this has got 512 Mb of RAM, so I've really got to take it easy).
Sometimes, though, it seems that if I "overwork" it somewhat, this strange thing will happen: I'll move a window, and suddenly it will seem as if the entire OS is frozen. But watching carefully will reveal that the screen is actually refreshing very slowly -- to the extent where I can visibly see the image on the monitor being drawn, almost line-by-line, from top to bottom.
This is rather bizarre from my perspective since the graphics performance of the system in general is fine. Most of the time, there is no visible sluggishness. So what's going on here? And more importantly, are there well-known steps one can take to fix this problem?
Mostly I'm just curious if anyone knows what the explanation for this graphical anomaly is.