SOURCE: syncmaster 913v not optimum mode
I just resolved this problem for my SyncMaster 913N.
It seems to be a known issue, however it can take quite some time for the problem to occur. In my case about 3,5 years, so well out of warranty.
Short term solution: unplug your monitor from power. The switch on the front is not good enough. Pull the plug and leave it for an hour or so (all night if you can). Good chance the monitor will work next time you power it up.
The problem will is likely to come back..
Permant fix requires some basic soldering as per this video:
I just managed it and it has been ages since I soldered a resistor so you may very well be able to do it. I spent $25 on tool and part and saved me from buying a new monitor.
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