harbir

Please give us the rest of your equipment details and settings

Check your BIOS and see if you have an onboard video chipset still enabled.

Make sure that you are connected to the physical outlet for the graphics card.

Look in hardware and see that the device is reported as working "properly"

Apart from "monitor" have a look in "adapter" (that is the graphics card) and see that it is showing the correct one and check the options there.

Look at what your colour settings and resolution are...................set the resolution to 800x600 and see if that gives you more options.

I doubt if you will get more than 75Hz refresh with a cheap LCD screen

As suggested, make sure that you have all the latest drivers for your videocard and monitor.