Pixel clock?

[Shoopman]

I was messing around with the EVGA pixel overclocking tool (dumb idea, but I did it anyway). I accidentally set my display to 70Hz, which turned out to be totally fine. However, when I went to go change it back to 60Hz I noticed that the software allows you to change not only the refresh rate, but also the pixel clock. The 60Hz settings has several available values for pixel clock, ranging from 138.7-140.9 MHz. Does this value even matter? How can I found the optimal setting? I set it at 140.0Mhz for now because it seems like a nice round number, but that was completely arbitrary.

 

Also, what does pixel clock even do? That would be nice to know.

[Peter Vaughan Truslow]

framerate in the EVGA pixel clock is based on the pixel clock, but the utility rounds down as far as I know, so 140.0 would be something like 60.6fps

my monitor ran at 77 hz but I couldn't set the HDMI black level to low during that and the blacks being gray wasn't worth a few more frames on my monitor.

[Shoopman]

framerate in the EVGA pixel clock is based on the pixel clock, but the utility rounds down as far as I know, so 140.0 would be something like 60.6fps

my monitor ran at 77 hz but I couldn't set the HDMI black level to low during that and the blacks being gray wasn't worth a few more frames on my monitor.

How are you arriving at that number? Should I set it to the minimum to hit exactly 60 fps?

[Glenwing]

Pixel clock is how the refresh rate is changed. A 165MHz pixel clock allows enough communication for 1920x1200 at 60Hz, higher is achieved by overclocking the pixel clock.

[Peter Vaughan Truslow]

How are you arriving at that number? Should I set it to the minimum to hit exactly 60 fps?

I'm estimating knowing that just because the utility says 60hz, it can be anything in the range of 60hz to 60.999hz for the utility to report 60 as the refresh rate is a function of pixel clock and resolution, and you are changing pixel clock to influence the refresh rate

[Mstief]

This is an old thread but I found it pretty easily so I'll reply for others. I think I figured out how to find refresh rate from the pixel clock rate.

If the pixel clock rate is 140Mhz, that's equivalent to 140,000,000 pixels per second. Find the number of pixels in your monitor by multiplying the resolutions. If your monitor is 1920 x 1080 the number of pixels is 20,736,000. Divide the pixels per second by the number of pixels. 140,000,000 / 20,736,000 = 67.5 is the max refresh rate.