Firstly i would suggest you to perform Self-Test Feature Check (STFC)
Your LCD TV when used as a computer display through DVI and/or VGA connection
provides a self-test feature that allows you to check whether your LCD TV is
functioning properly. If your LCD TV and computer are properly connected but
the LCD TV screen remains dark, run the LCD TV self-test by performing the following
- Turn off both your computer and the LCD TV.
- Unplug the video cable from the back of the computer. To ensure proper Self-Test
operation, remove both Digital(white connector) and the Analog(blue connector)
cables from the back of computer.
- Turn on the LCD TV.
- The floating 'Dell - self-test Feature
Check' dialog box should appear on-screen (against a black background)
if the LCD TV cannot sense a video signal and is working correctly.
While in self-test mode, the power LED remains green and the self-test
pattern will scroll through the screen continually
This box also appears during normal system operation if the video
cable becomes disconnected or damaged.
Turn off your LCD TV and reconnect the video cable; then turn on both your
computer and the LCD TV.If your LCD TV screen remains blank after you use
the previous procedure, check your video controller and computer system; your
LCD TV is functioning properly.
OSD Warning Messages
A warning message may appear on the screen indicating that
the LCD TV is out of sync range.
See Specifications for the Horizontal and Vertical frequency ranges
addressable by this LCD TV. Recommended mode is 1280x 768 @ 60Hz.
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