Hi!! every bodyplz help me out...when i boot my pc it start and after logging, screen is flickering...so to stop this i needto increase refresh rate and for this i go to control panel=> select display=>select setting=>click on advance=> click on moniterits showing properties as diable and screen refresh rate as "use hardware default setting"when i click on it , there is no option except "use hardware default setting"is anyone tell me how can i change my refresh rate.. and their check box is also disble..