[X4U] Mac mini doesn't like 20" widescreen

[Joe Sporleder]

Here's an interesting problem. I have a small publishing company.  
Sometimes we use PowerMac G5s when we need extra horsepower and  
extended desktop monitor support. At our less intense workstations, a  
Mac mini with a 17" LCD or 20" widescreen works great when the budget  
is tight.

I have 2 Acer 20" widescreen displays and a Viewsonic vx2025wm 20"  
widescreen, optimized for 1680x1050 resolution. These monitors will  
connect fine via DVI (haven't tried the problem computer on VGA) to a  
PowerMac G5 DP 2.0GHz. Also connects fine to a Mac mini with 1.5Ghz  
G4 and a coworker's personal home Mac mini 1.25Ghz. However, a 2nd  
Mac mini 1.25Ghz at a remote office purchased a few short months  
after the coworker purchased hers (from my recommendation) will not  
drive the 20" widescreen displays. All of the Mac minis have at least  
512MB of RAM (G5 has 2GB) and all machines are running MacOS X  
10.4.6. The problem Mac mini is drivng a 17" ViewSonic via DVI just  
fine. It simply refuses to display on the 20" widescreens. The  
ViewSonic widescreen does flash an "Out of Range" message on the  
screen. Resetting the PRAM didn't help, as suggested on a discussion  
forum at Apple.com.

Any ideas why 2 Mac minis that appear to be the same generation, one  
runs the 20" widescreens mention above just fine, and one doesn't?  
Any other things I should reset? How about the PMU?

Joe