I don't use ATI card. So, I can't exactly tell you where exactly you can find the option. But look around the monitor tab, there will be another tab for "ATI Display" or something like this. Under that tab you'll find another option for monitor (probably under "Displays" option/tab). Click on that where you can set resolution and refresh rate for your card. You have to set both monitor options same - one on that page and another what you've already done on regular Windows Monitor tab.Quote from illiquid:
I dloaded latest drivers, but I still can't seem to change the refresh rate under MONITOR tab, I can adjust it under the ADAPTER tab but under monitor it still shows 60mhz.