input and output different?

[1337voltronBOT]

Now im sure somebody has asked this somewhere. I think my wording is what is throwing google for a loop and not letting me find anything. but basically when i look at the osd on my monitor it shows this exactly:

INFORMATION

1920 x 1080
H: 158KHz V: 144 Hz

VIDEO OUTPUT
1920 x 1080
H: 157khz V:143Hz

DVI INPUT

What in the world does this mean? does it mean something is out of sync? Does it mean they are always off and i never heard mention of it? why are these two values different? Does it take 1KHz to get from my graphics card to my monitor?

The Monitor is a
Acer GN246HL Bbid 24-Inch 3D Gaming Display (144Hz Refresh Rate)

the graphics card is a GIGABYTE WINDFORCE 1050TI 4GB OC

OH! i almost forgot. I am hooked up via Dual Link dvi. i couldnt tell you if its i or v or digital or analog or what i just know i got a 144hz refresh rate option so im doing something right.

Thanks for spending your time on my noob question : )

[Chief Blur Buster]

KHz is simply the horizontal scanrate is simply the number of pixels rows per second transmitted over the video cable from the computer to the display. A 1920x1080 signal at 144Hz, plus about 2% extra for a reduced blanking interval (the VSYNC signal that tells the monitor to begin a new refresh cycle) would mathematically be: (1080p x 144 Hz x 1.02) = 158630 pixel rows per second = 158.6 KHz horizontal scan rate for 1920x1080 at 144Hz, including the hidden blank rows of pixels representing the VSYNC signal.

(BTW: Interesting fact: If you've seen an defective/misadjusted old 1960s or 1970s TV with a rolling black bar -- from a VHOLD dial misadjustment -- the black bar is the "VSYNC" SIGNAL. This blank synchronization signal between refreshes is only a few percent of the picture height -- even modern monitors still requires a VSYNC signal between refresh cycles to this date, including on digital cables (DVI, DisplayPort, etc).

Now, the differences between two numbers is usually caused by math rounding errors when the monitor is trying to display statistics, sometimes caused by the graphics card outputting a fractional refresh rate (e.g. 143.9Hz). So nothing is actually out of sync, as long as the monitor is functioning normally. Unless you're seeing unusual frame-skipping (like exactly 1 frame skipped per second). You can use a Custom Resolution Utility to raise/lower refresh rates in fractions, but if this is simply a statistics-display-only rounding error that only affects the monitor menus (and not actual display/graphics/gaming/motion) -- then I wouldn't worry about the difference.

[1337voltronBOT]

Well its really hard to tell. because when i run at 144 hz it seems fine. if i can maintain. but especially when playing games at 60 hz on this monitor it seems to hickup really bad. like almost in a patern like way. its like there s hickuping everysecond. is this a problem with running 60z on 144hz monitor? oh i wanted to add to that i do get some silly frame rounding in my games. for instant vsync at 60 hz never displays 60hz. its always either 59 or 58. quake live does this. also star craft 2. even if i turn vsync on and frame limit at 60 fps at 60hz it seems to lock at 58 or 59. but i dont think thats a problem with the gpu monitor combo because my old monitor refused to lock at 75 hz too. very weired.

[Chief Blur Buster]

If you add a manual frame-rate cap, it will often never exactly match the monitor's refresh rate, and will often hiccup occasionally.

If hiccups disappear at VSYNC ON, there's no problem with your monitor.

Try TestUFO too (close all browser windows first, and all applications)
Visual motion test -- http://www.testufo.com and http://www.testufo.com/photo
Frame Skipping test -- http://www.testufo.com/frameskipping

It will be extremely difficult to capture a skipped frame if it's only 1 per second, but you can take several long camera exposures -- and see if any of them show the frame skipping. TestUFO will naturally occasionally skip randomly, but if you see a metronome-style skipping that always happen every 1 per second, that's a dead giveaway your monitor is frame-skipping.

However, there are many situations other than the monitor/GPU where perfectly regular metronome-style frame skipping occurs (like 125Hz mouse at 120Hz display refresh rate = 5Hz beat-frequency skipping that can be fixed with a 1000Hz mouse, see Blur Busters Mouse Guide). And of course the frame cap too.

Also, it could be Windows background tasks too -- try booting windows without your system tray applications temporarily (some of them run housekeeping tasks every exactly 1 second, causing forced frame skips)

If the off-by-1 bothers you a lot, try going to your Custom Resolution Utility (NVIDIA/AMD, or even the third-party ToastyX Custom Resolution Utility) -- and raising your refresh rate slightly to 60.1Hz (for 60Hz), 120.1Hz (for 120Hz) and 144.1Hz (for 144Hz), and see what happens. But I do not recommend doing this, as if you already are using a 144Hz monitor, then I'm 99% sure your monitor isn't the device that's causing the frame skipping. This tweak simply helps statistics to round-off better (e.g. 60.1Hz will rounddown to 60Hz, unlike 59.99Hz which might rounddown to 59Hz) even if there's absolutely zero effect on frameskipping (except for possibly defective framerate capping features that doesn't handle fractional framerate capping).

[RealNC]

You can detect your actual refresh rate here:

https://www.vsynctester.com

[Chief Blur Buster]

You can detect your actual refresh rate here:

https://www.vsynctester.com

Excellent idea, I'll add this to a future version of TestUFO Motion Tests (see TestUFO Suggestons Thread).

I am very familiar with their test, they actually link to Blur Busters too, as they found our information helpful in creating this type of test for more precise browser troubleshooting. But it's happening to be very useful to measure precise refresh rate.

For simplicity, TestUFO intentionally rounds-off this number but there's a need for a special TestUFO test that displays an exact refresh rate.

[Q83Ia7ta]

You can detect your actual refresh rate here:
https://www.vsynctester.com

BenQ XL2540 if someone interested:

wee.png (54.53 KiB) Viewed 4563 times

[1337voltronBOT]

does your hz bounce around alot on that test?