The Matrox G550 card in use here have a VGA output on head 1 and a DVI output on head 2. (At least I guess those are 1 and 2). When booted with only a device attached to the DVI output, it seems to switch to this at boot time and all console output is at the DVI-out. In this situation the mga driver (without HALlib) generates too low vertical refresh rates. (The driver says it uses 60Hz, but the TFTs either say out of range or the better model show something about 29 Hz) Adding another output device to the VGA output also shows wrong frequencies then.
*** This bug has been marked as a duplicate of 4249 ***
I believe I'm seeing the same problem on a G550 dual dvi (the card has one DVI connector, but with that dual dvi cable you can connect two DFPs). When I start X, the monitor says the frequencies are out of range. Not sure how to test what frequency the driver is trying to use. Switching off the monitor and switching it on again "fixes" the problem. Not sure whether that means I'm slowly frying my monitor that way though. The patch from #4249 does not help here.
Disregard my comment above, it has nothing to do with Bernhard's problem. *** This bug has been marked as a duplicate of 4249 ***
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