My aoc model 729 lcd monitor displays windows start up but then says there is no signal.

A loose connection between your monitor and your PC will trigger the monitor no signal issue. If you're seeing the no signal message on your screen when your Windows system is running, the first thing you should check is whether your compatible video cable is firmly connected or not

Plug in the power and connect the display cable to your computer

Sounds like its T'Con board fault. If you wish to get some details; check the site linked here. Pull up older posts.
http://electronicshelponline.blogspot.com/
Line faults & possible causes to LCD is given with illustrations. You can get an idea about the fault to an extent. Faults to all LCD & Plasma screen are similar, irrespective of its brand and screen size.
Search the site by type in the "brand name" to your device; (Exclude the model number), in the "Search box at the top right of the display window of the Homepage" to get gathered related posts.

check for loose contact at the VGA port or replace VGA cable. if won't work, check for bad component parts at the lcd controller board like open resistance or replace the board will solved the problem.

This sounds like a computer problem and not really a television problem. Check your driver files.

Try removing your driver files. Then disconnect your AOC monitor. Reboot the computer and login. Shut down the computer and reconnect the AOC monitor. Start the computer. Now install the monitor drivers.

It sounds like there is no signal to the monitor. The computer you have, does it work if you hook up another monitor? Have you taken this monitor to maybe a friends house or neighbor? See if it works. If it does; there may be a problem with your computer's video. If the monitor does not work; the issue is the monitor. It will then need to be replaced.

hi

Depending on the brand and model of your monitor, there may be extra features that require special troubleshooting tips, or there may even be alternate ways of troubleshooting basic problems. For this reason, it is important to keep your user manual.

If you have come across an issue with your LCD monitor that cannot be corrected through the basic settings, you should consult the user manual to determine troubleshooting solutions for your specific monitor.

For example, The AOC 175F LCD monitor features a 90-degree rotating display, which, in order to rotate correctly within Windows XP, must have AOC's third-party software installed. This is not something required of all LCD monitors, as not all LCD monitors offer a rotating display.

If the troubleshooting section of your user manual still does not solve the problem, it may be necessary to contact the manufacturer's support team (via phone or web) to discuss what is wrong with your monitor

check RAM or replace it

Most probably failure in the LCD controller IC in the lcd controller board. that no signal was sent out to the lcd driver ic thus you could only see white display on the screen. A replacement of LCD panel might be the solution. regards

I've had a very similar issue on many Dell Monitors. Mine have been under warranty and they usually send me a new monitor, but I believe the issue lies with the power supply within the monitor.