is the first sentence supposed to say "video cards" rather than "monitors"? had to read this several times to make sense of it.

the monitor OSD will tell you what refresh rate it's getting, and the monitor also is where frame skipping would most likely be introduced, due to things like having to support 70hz BIOS screens on 60hz panels. it will not tell you if it's frame skipping, but this should be verifiable easily enough with a scrolling test.

i don't know if there is any graphics hardware out there that frameskips higher refresh rates just to be able to present these options, but that would be really bad practice. again, if such a thing exists, comparing different refresh rate settings with a scrolling test would show it.

auron wrote on 2025-03-12, 16:57:

is the first sentence supposed to say "video cards" rather than "monitors"? had to read this several times to make sense of it.

The sentence is correct, I do mean monitors.

What I'm trying to ascertain is that if a monitor says it's getting a 75Hz signal, is that signal what is being displayed by the panel itself.

the monitor OSD will tell you what refresh rate it's getting, and the monitor also is where frame skipping would most likely be introduced, due to things like having to support 70hz BIOS screens on 60hz panels. it will not tell you if it's frame skipping, but this should be verifiable easily enough with a scrolling test.

i don't know if there is any graphics hardware out there that frameskips higher refresh rates just to be able to present these options, but that would be really bad practice. again, if such a thing exists, comparing different refresh rate settings with a scrolling test would show it.

I know there is a software tool for testing 70Hz versus 60Hz. I'm wondering if anything else exists to test other refresh rates, or if anyone has a process to test such rates.

After doing some more Googling, I came across various sites that use HTML5 to test refresh rates, such as: https://www.testufo.com/refreshrate

Not entirely sure how accurate these are, but at least its something. Obviously won't work under XP or earlier, given browser tech of the time.

What I really think I want is something similar to the 70Hz test with a scrolling bar, and then using a camera at a fixed shutter speed (maybe 1/2 second exposure) to capture what is being rendered. Then it's easy to see if frames are being skipped.

edited to add:

The above test doesn't account for frameskipping. Instead, this test can be used: https://www.testufo.com/frameskipping

If the monitor says it's getting 75hz, there's no reason to believe that it isn't.

brian105 wrote on 2025-03-20, 16:32:

If the monitor says it's getting 75hz, there's no reason to believe that it isn't.

Just because a monitor accepts a particular input signal doesn't mean it is physically displaying at that refresh rate. 60Hz displays for example will typically accept a 70Hz signal (for DOS VGA resolutions), but the monitor skips rendering every 7th frame to output only 60Hz to the panel.

To once again update my own thread, I found this tool for specifically testing frame skipping (runs in a browser): https://www.testufo.com/frameskipping

I have noticed the previous refresh rate test I linked doesn't seem to take into account frame skipping.