I have a mini display port output on my laptop and a 27" widescreen LCD monitor that takes in DVI (dual link I presume). To rectify the issue, I purchased a display port to DVI dual link adapter. However, when I plug everything together, the 27" LCD monitor doesn't seem to be able to do any resolution other than 640x480. After two or three weeks of being plugged in, one day, the monitor all of a sudden started displaying the proper resolution of 1920x1200 and I have not changed anything (not even rebooted).
Overjoyed, I used my new monitor for over a month and all was good.
Recently, I went on a rather long trip and took my laptop with me. After coming back, I plug my cables back in and now my silly monitor is back to 640x480 resolution again with no way of changing it. I'm going to leave it plugged in again for a few weeks to see if it suddenly works again.
What is causing this and how do I fix it?
My laptop output - display port Adapter input/output - display port/dvi dual link Monitor input cable - dvi-i (yes, I know its not a dual link cable) OS - Windows 7 ultimate
I know DVI-I can support the standard 1920x1200 resolution, so the cable to the monitor (that it came with) doesn't have to be dual-link capable, and it did work for a month some how, (my guess is voodoo magic), but I would like to know why its doing it.
Since I asked the question, I have left my laptop plugged in and now this morning I notice that the resolution of my monitor is now correct. The only thing I did today was wake it up from sleep.