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One of my clients is running RHEL 5.5 Client (aka workstation), paid-up with support. He has a multi-monitor setup using xinerama. The video card is a nVidia Quadro NVS 250. This problem occurs both with the latest-avilable video driver from the computer vendor (who happens to be Dell), and with the latest-available video driver from NVidia (2 August 2010, downloaded today).

When he runs a specific CAD tool, he sometimes observes apparent video problems, specifically:

  • sometimes windows don't repaint themselves when brought to the front, they end up with the previously overlaying display still on the window. The user has to manually refresh the window. The specific circumstances which lead to a repaint failure are reproducible, however in general this does not happen (ie it only appears to fail under specific sequences of events).
  • With a specific window, if he moves it from his primary display to his secondary display, the window loses the fonts on the menubar (File, Edit, Help, etc) and the menus themselves. The menus are still present, if you click on the window where they are supposed to be, the blank button highlights and the menu of blank options drops down where you can select them. If you move the window back to the primary display, you can get the fonts back if you resize the window slightly.

Before I get the Cad-tool vendor and Redhat blaming each other for this problem, does anyone have any ideas what is going on and how I might fix it?

share|improve this question
Silly question, but has he tried swapping the splitters on the outputs? I know he's only getting this problem in specific circumstances but those 59-pin connectors are so goddamned finicky that I feel it worth at least mentioning. – Shinrai Aug 4 '10 at 22:51

I'd suspect the video card. Since you say you have a reproducible scenario to get (one of) the problems to show up, I'd try a replacement video card first (of the same make and model) and see if that matters/helps.

Also, sometimes CAD programs require/supply specific video drivers. This occurs a lot less these days, but it's probably worth looking into with your CAD software vendor.

share|improve this answer
Hmm... I just happen to have an identical system available. I'll build it up and see if the problem is reproducible. – David Mackintosh Aug 5 '10 at 14:08

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