A monitor has three timing components, the pixel clock, the horizontal scan rate and the vertical refresh rate. The vertical refresh rate, also called the vertical frequency, vertical scanning frequency, or simply refresh rate, is a measure of how many full screens the monitor draws per second and is given in hertz (Hz). The horizontal scan rate is the time it takes to draw one horizontal line across the screen. The pixel clock is the time it takes to draw one pixel. Faster refresh rates require faster horizontal scan and a faster pixel clock.
Jim Witkowski
Chief Hardware Engineer
Cornerstone / Monitorsdirect
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