Windows 7 Forums
Welcome to Windows 7 Forums. Our forum is dedicated to helping you find support and solutions for any problems regarding your Windows 7 PC be it Dell, HP, Acer, Asus or a custom build. We also provide an extensive Windows 7 tutorial section that covers a wide range of tips and tricks.

Windows 7: [INFO] - Flickering monitor not connected to KVM

17 Sep 2013   #1
Mr Davo

Windows 7 (XP, by Virtualization)
[INFO] - Flickering monitor not connected to KVM

Hi Everyone,

I am running a Windows 7 computer, with a 3 monitor setup. The centre monitor that I use is a Shimian (2560 x 1440) and I have satellite monitors Dell (1920 x 1080) on the left and right sides.

When I came into work yesterday I was shocked to see the following (please watch this YouTube video) of my monitors...

Strange Monitor Behaviour

My first instinct was that perhaps something was wrong with the Shimian monitor, or the graphics card. However after performing some diagnosis I came to the conclusion that a KVM that I had plugged into the right satellite monitor was the source of my grief!

I find this particularly interesting because the Shimian is connected by HDMI, and had nothing to do with the KVM! My left satellite monitor connects by mini DisplayPort, my centre monitor connects by HDMI, and my right monitor did connect by KVM switch.

I can only conclude that the KVM was causing the graphics card to overload, and as a result affecting the output on alternative video connectors (i.e.: HDMI, mini DisplayPort).

Here are some shots of my old KVM for interest sake -

I have written this post in the hope of helping others who may be experiencing display issues related to a KVM, and to let people know that a monitor doesn't have to be plugged into a KVM to be affected by the presence of a KVM on a multi-monitor system.

Please don't take this as a warning off KVM switches, or a slant on any particular KVM brand - I did use the pictured KVM happily for several years before this happened.

Kind Regards,


My System SpecsSystem Spec
18 Sep 2013   #2

Winndows 7 32 bit

Hi Davo,

Thanks for this insightful information. I am sure it would help other users as well facing the same issue. Quite a strange diagnosis that KVM for different monitor is causing flickering on monitor connected with different port.

Thats why they say troubleshooting is about thinking outside the box.:)
My System SpecsSystem Spec

 [INFO] - Flickering monitor not connected to KVM

Thread Tools

Similar help and support threads
Thread Forum
Flickering lines suddenly appearing on my HDTV connected to my RIG ...
Just today,i noticed some strange flickering lines appearing on the corner of my screen.And after sometimes , these lines are spreading to other areas of the screen. I have tried removing any metallic or magnetic objects near my screen.Since , that causes these lines sometimes near the...
Graphic Cards
flickering monitor
Hi Everyone, I need Help my monitor just keeps on flickering at Bootup and even at the start up of the OS.... can Someone help me? I am using a SiS mirage 3 graphics. i don't really know what caused the problem...(P.S. Im still a newbee, my cup is empty ^_^)
Hardware & Devices
black flickering GTX 460 BSOD info
I also noticed it flickering lot's to the point of freezing really quickly in starcraft II with the graphics on ultra. Fresh install only a few days old. Attached BSOD zip.
BSOD Help and Support
monitor flickering
windows 7 32 bit with GA-MA785GM-US2H - GIGABYTE motherboard which has onboard ATI Radeon HD 4200 graphic. Monitor is Qptiquest Q20wb. I have installed latest ATI driver. Refresh rate is stuck at 59hz on windows monitor properties and it shows 60hz on the ATI Catalyst properties screen. I...
Graphic Cards
flickering INFO panel
Hi all, Have a strange problem. Live TV and videos etc. all work fine. The only problem I'm having is with the Synopsis panel that displays in the center of the screen and gives you for example the option to record a show will flicker. I am running Windows 7 86x on a 3.6 ghz PC with 2g ram,...
Media Center

Our Sites

Site Links

About Us

Find Us

Windows 7 Forums is an independent web site and has not been authorized, sponsored, or otherwise approved by Microsoft Corporation. "Windows 7" and related materials are trademarks of Microsoft Corp.

Designer Media Ltd

All times are GMT -5. The time now is 16:21.
Twitter Facebook Google+