Why does my Coretronic Corporation LCD monitor only display in 800x600?

You didn't say if you installed the drivers, or if Windows just picked it up and installed them itself. It's possible the proper drivers aren't installed for it. If you can't adjust the settings in the monitor panel to higher than 800x600, then that's the case. It can be HARD to find the drivers for obscure brands online, I do know that. If you bought it used, and never saw it working, then maybe the video board is bad in it, or the connections have loosened up inside. If it's the drivers, there's a CHANCE that it was sold under another brand name in which case those drivers will work. I've had to do that with a couple monitors for people. I found this online, if it's of any help:

Founded in 1992, Coretronic was originally called CTX Opto and was the first company to offer LCD backlight and VGA modules in Taiwan. In 1993 and 1995, the company introduced a VGA analog input LCD Monitor and a VGA projector under 10 pounds. The year 1997 represented a milestone for Coretronic: the company's expertise and excellence in the LCD field helped it win the OEM business to manufacture LCD monitors for two global customers. Coretronic continued its ambitious expansion in the following years, moving into its current Hsinchu headquarters in 1998, becoming a public company on Taiwan's OTC market in 1999. In January 2000, the company's English name was changed to Optoma Corporation. Coretronic has successfully established its Mainland China facilities in 2000. The name of the company was further changed to Coretronic in December 2001 in order to be separated from the Optoma brand name and allow Coretronic to focus on the OEM manufacturing business.

I hope this is of some help. Good luck! ;)

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