On Mon, 2006-12-11 at 11:20 -0800, ols6000@xxxxxxxxxxxxx wrote: > At 10:59 AM 12/11/2006, you wrote: > >There isn't even a software capability to make that occur. > > There is a warning in the monitor docs not to set the frequency and > resolution out of range, as it can cause physical damage to the monitor. > > The monitor was definitely working before the FC6 install, and > definitely not afterward. During the install, the screen went blank > and stopped responding to any signal (not just Linux). > > > What is the bug# > > I did report this as a bug, #218416. > I have destroyed several monitors this way (I have been programming a long time, and hacked a lot in my early years), but I never saw the interface itself go bad. What happened was that the flyback (the circuit that produces the high voltage for the CRT) will collapse and cause a voltage spike taking out the diodes, the screen goes black and that's it. The monitor is done until you replace the HV supply (and reset the video sync frequencies). Most of the newer monitors use a different form of syncing, and the monitor HV supply will default to a lower frequency if possible (the early ones used the horizontal sync pulse to synchronize the HV supply to sweep the beam, most newer ones use a separate source for the horizontal sync signal, and while it might be possible to cause the deflection coils to do something similar, it is not likely). But the interface itself is independent of the HV supply and would not suffer from a frequency problem. However, a hot plug situation could cause a spike in the input that could fry the buffers and the input circuit would be dead. In the old days, the buffer was separate, something like an opamp chip and you could replace a single 16 or 20 pin device and be back on the road. However today things are typically more integrated and you may have an expensive repair (several tens of dollars for the component and typically 60 an hour for a capable tech for the high density multilayer boards. Regards, Les H
