Display resolution not sticking at boot

When users have problems with hardware settings, many times the solution is to reset the PRAM; however, for some users this has introduced some other minor problems.

Apple Discussions poster AdiosVistawrites: "I was having a weird graphics issue and one step I took in troubleshooting, as told to do by Apple over the phone, was reset the PRAM. Now every time I boot the Mac Pro, the white and grey apple screen is stretched and looks to be around 800x600 while my monitor resolution is 1920x1200."

When the system loads to the point of login or to where the login window displays, the screen resolution resets normally, but it can be a little irritating to have the screen reset like this.

When users reset the PRAM, they clear settings that include the default system settings that load before the operating system loads and passes new settings to them. These settings include the startup disk which can result in longer boot times if improperly set, the mouse speed, and the screen resolution as described above. In order to fix this problem, users should go to their system preferences and manually reset the problematic setting.

Fix: Manually reset the settings In the case of screen resolution, users should go to the "Displays" system preferences and try clicking the "Detect Displays" button to have the system reset and rediscover the display settings. Additionally, setting the display to another resolution besides the screen-native one, and then changing it back should change the settings as well. The system may need to be restarted between these settings changes. If these settings still do not change, users might try resetting the PRAM again, and hold they keys down for several reset cycles to ensure the parameters are fully cleared.

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