Question Waves going down my screen

Sep 9, 2019
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I got a KVM switch and am using it to switch my keyboard+mouse to a secondary PC that has its own monitor (plugged into the on-board graphics). So the only things the KVM is plugged into are usb ports.

As though it's causing some interference, it's causing my secondary monitor to display waves of brightness traveling down the screen. I went to display properties and reduced the refresh rate from 60 to 30, (I misremembered that there wasn't a 30Hz option)
I changed the resolution and that changed the speed of the waves, but can I eliminate it completely? Is this bad for my monitor?
 
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Mrgr74

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Sep 2, 2019
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I got a KVM switch and am using it to switch my keyboard+mouse to a secondary PC that has its own monitor (plugged into the on-board graphics). So the only things the KVM is plugged into are usb ports.

As though it's causing some interference, it's causing my secondary monitor to display waves of brightness traveling down the screen. I went to display properties and reduced the refresh rate from 60 to 30, and that slowed the waves down, but can I eliminate it completely? Is this bad for my monitor?
So it looks like old CRT monitors in movies, where the refresh rate was different and so you saw the scrolling effects? :)
What type of onboard do you have? Updated drivers?
What happens if you completely remove/power down the KVM switch? Plug your KB&M directly into the PC connected to the monitor with the refresh issues.
Lower the resolution to 1280x1024 and set the hz to the highest your monitor will go. Do you still see the refresh lines?
 
Sep 9, 2019
4
0
10
0
So it looks like old CRT monitors in movies, where the refresh rate was different and so you saw the scrolling effects? :)
Almost, it's not the whole image that's scrolling down the screen, it just looks like waves of brightness. I'd take a screenshot but...
What type of onboard do you have? Updated drivers?
Drivers are indeed the latest at 8.15.10.2629
Name: Intel G33/G31 Express Chipset Family
Chip Type: Intel GMA 3100
Approx. Total Memory: 256MB
Display Memory: 0MB
Shared Memory: 256MB
Monitor: Generic Pnp Monitor
HDR: Not supported
DirectDraw, Direct3D and AGP Texture Accelerations: Enabled
What happens if you completely remove/power down the KVM switch? Plug your KB&M directly into the PC connected to the monitor with the refresh issues.
There is no way to power it down, however, the moment either plug feeding either PC is disconnected, the waves stop. Plugging the kb+m directly doesn't cause any issues.
I NEGLECTED TO SPECIFY A DETAIL ABOUT THE KVM SWITCH
While it takes the kb+m usb inputs, the outputs are only VGA ports. Plugged in these ports are what're called KVM cables, VGA on one end to take inputs (video, kb+m, mics &/or speakers) that, toward the PC end, split into VGA+USB. So when I say I disconnect either plug, I mean these VGA plugs (from the KVM end, the VGAs aren't plugged at the PC end). I don't have another VGA input to try plugging it in & seeing if that makes a difference. I have of course tried switching cables around and plugging into different usb ports.
Lower the resolution to 1280x1024 and set the hz to the highest your monitor will go. Do you still see the refresh lines?
So, I updated my OP to correct myself: there isn't a 30Hz mode. However, changing the resolution did affect the wave frequency to varying degrees without a clear pattern. Going up from the lowest res, the waves were fast, then slow, then slightly faster, slightly faster, slightly faster, superfast, slow again etc.
I found a 75 Hz mode that makes the wave frequency higher and speed faster, a 59Hz mode that made the frequency way lower and speed slower, & a 56Hz mode that made the waves pretty much like the 75Hz mode.
1280x1024@60 made the waves slightly faster. 1280x960@75 (nearest available at 75), the frequency was superfast.
o_O

Update: In fact, just turning off my main monitor (a 30" 2560x1600) stops my second screen's want problem. FML
 
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