Is there not a menu button on the monitor? How old is this monitor? If it's less than 6 years old, it should definitely have an on screen display. Look for a button labled OSD, or Menu. If it's a new monitor, did it not come with an instruction booklet that would show you how to access the osd? What brand and model number is this monitor? There might be online documentation for it.
To adjust the refresh, go into your display properties (Control Panel > Display), click on the last tab which should be Settings, then click the Advanced button. Now you should see a set of tabs, one's probably Adapter, another Monitor, and so on. The refresh is usually under either Adapter or Monitor. It'll be a pull down list ... generally defaults to Adapter Default, or 60Hz depending on the adapter, and if the drivers are installed correctly. Pull that list down, and if you see a list of numbers, click on one of them (at least 75Hz, but higher if your monitor can handle it). Then just Apply or OK your way back out, and you should be good to go. If the screen goes funky and unreadable, just wait about 20 seconds, and it should revert back. If that happens, that means the monitor can't handle the refresh you set coupled with the resolution you're running. Try a lower refresh and see if that works.
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