My LCD monitor (SyncMaster 720N 17") flickers too much.Refresh rate is 75Hz,resolution 1280*1024,drivers are ok,dont know what to do?please help!!!!!!!!!!!!!!!!!!

Your graphics card will not support that refresh rate @ 1680x1050. you may need to upgrade your graphics card.

Here is the best price/performance card for your machine. and will support upto 2048x1536 @ 85Hz

Hope this helps.

http://www.scan.co.uk/products/512mb-pny-nvidia-geforce-6200-graphics-card-agp-8x-4-cores-d-sub-dvi-i-s-video-passive-cooling

Most LCD manufacturer recommend 60Hz, all the LCD monitors (close to 100, 2 monitors per work station) at my office are set to native resolution and @60Hz, LCD refresh rate does not work the same as the old style CRT. You can tell by using the digital camera to see if the screen is flickering or not, point the camera at the CRT monitor and you will see the screen will be rolling but not on hte LCD screen. Try this monitor with other PC.
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1280x1024 native and will go to 75hz x 81khz
I'd probably look more at what your video card supports.

Try to adjust the refresh rate of the screen
Display settings / advanced settings / Monitor refresh rate (should be between 60-75hz I think)

You can connect it to your old monitor. As a safe method before connecting the lcd monitor to the old system go to ---- control panel --- display. Double click on it and select settings ----- advanced

Here select - monitor---->monitor settings ---> screen refresh rate. Select a low refresh rate (60 or 70,72). Press apply then ok.

Switch off the pc and remove the old monitor and connect the lcd monitor. It will work.

1: Signal out of range meas the monitor can't handle the input refresh rate. lcd and Tft monitors usually supports 60 and 75Hz refresh rates.
2: The Resolution you are using to view the desktop is too high, this number is depending on the size of the lcd monitor.
a 15" lcd usually runs with: 1024x768 with 60hz
a 17" lcd usually runs with: 1280x1024 with 60hz some of them supports 75hz.
a 19" lcd usually runs with 1600x1200 or higher.

I recommend reading the user manual if you have it, or checking the information on the manufacturer's website.

3: As a solution turn on your computer and after it passes the bios screen press F8 and select VGA mode.

This will enable 640x480 (standard vga) resolution and 60Hz refresh rate, after windows boots up you can change thease nmbers , and windows automatically asks for turning to 800x600 60Hz.

If you want to change the resolution go to: Right click on your desktop, select properties , select settings tab, and adjust the resolution on the bottom of the window.

Hope this helps, good luck.

Does the monitor remain on does it switch off?
Problem seems to be hardware related ie monitor itself is defective.Try connecting to another known working system.If monitor is defective it could be a power/inverter related issue or panel could be defective.
Please provide feedback and rate the solution.
Samir

video card may not be capable of that resolution and color depth, check your video cards max resolution and color depth.
I have several lcd monitors that are 1280x 1024 and they do not need drivers to work. the video card must be capable of generating that resolution.

a) set your screen resolution to 1024 x 768 and then b)go to desktop( right click) properties -->settings--->advanced--->monitor---> change the refresh rate to 72Hz or 75Hz.

no,
the LCD display don't harm the eyes cause don't spreed radiation.
preferred resolution 1280x1024 at refresh rate of 60Hz is not optimal.
the samsung 710N can easy handle 75Hz at 1280x1024 so just change it.