2005FPW Image Setting problem (aspect ratio)

I have a 2005FPW being driven by an Intel(R) 82852/82855 GM/GME Graphics Controller that can apparently only do 1400x1050. Since I got the display, I've set its Image Setting -> Scaling to Aspect, and it's nicely filled the display except for the two small black bands on either side.

Something happened last Friday -- I don't know what -- and now it's firmly in Fill mode, with no black bands but a distorted (overly wide) display. I've tried setting the monitor to 1-1, Fill, and Aspect, but nothing changes. I've checked the computer, and I can't find any pertinent settings in the display driver (I'm running Intel Driver Version 6.14.10.4497). Has anyone seen the 2005FPW get stuck in one Image Setting mode, and is there a way to get out of it?

Thanks.