homepage Welcome to WebmasterWorld Guest from 54.145.243.51
register, free tools, login, search, pro membership, help, library, announcements, recent posts, open posts,
Become a Pro Member
Home / Forums Index / Hardware and OS Related Technologies / Webmaster Hardware
Forum Library, Charter, Moderator: open

Webmaster Hardware Forum

    
KVM Switch Automatically Changes Screen Resolution
engine

WebmasterWorld Administrator engine us a WebmasterWorld Top Contributor of All Time 10+ Year Member Top Contributors Of The Month



 
Msg#: 3322469 posted 1:33 pm on Apr 25, 2007 (gmt 0)

I added a KVM switch to control two PCs.

As soon as I boot up when the KVM switch is attached, the resolution changes to 800 x 600. Unplugging the KVM switch and connecting direct to the keyboard/mouse/monitor, and it reverts back to the original settings.

Why does this happen?

Obviously, I have changed the resolution back to the original while the KVM switch is attached.

 

Marcia

WebmasterWorld Senior Member marcia us a WebmasterWorld Top Contributor of All Time 10+ Year Member



 
Msg#: 3322469 posted 11:14 am on Apr 26, 2007 (gmt 0)

What is a KVM switch?

engine

WebmasterWorld Administrator engine us a WebmasterWorld Top Contributor of All Time 10+ Year Member Top Contributors Of The Month



 
Msg#: 3322469 posted 2:22 pm on Apr 26, 2007 (gmt 0)

Keyboard Video Mouse switch enables control of multiple computers from a single keyboard, mouse and screen.

[en.wikipedia.org...]

Strange thing is, I have never had the problem of the resolution changing on a hardware KVM switch before.

coopster

WebmasterWorld Administrator coopster us a WebmasterWorld Top Contributor of All Time 10+ Year Member



 
Msg#: 3322469 posted 1:16 am on Apr 27, 2007 (gmt 0)

Depends on the relationship between the switch and the OS (read: drivers). See if there isn't a driver update for your OS.

jtara

WebmasterWorld Senior Member jtara us a WebmasterWorld Top Contributor of All Time 5+ Year Member



 
Msg#: 3322469 posted 3:10 pm on Apr 27, 2007 (gmt 0)

Sounds like the KVM is either not passing-back or not caching DDC, and your OS is configured to use DDC to set the monitor resolution.

DDC is a signaling standard that allows your monitor to tell the computer it's resolution and other characteristics.

I would first make sure that when you reboot, you've switched the KVM to that computer. If that doesn't work, you'll have to configure your OS to explicitly set the resolution, rather than using DDC.

engine

WebmasterWorld Administrator engine us a WebmasterWorld Top Contributor of All Time 10+ Year Member Top Contributors Of The Month



 
Msg#: 3322469 posted 6:03 pm on Apr 27, 2007 (gmt 0)

Thanks for the tips.

The KVM is switched to that machine, and it has all the latest drivers. Both machines are using XP Pro SP2 and the second machine works just fine.

But then, these things happen, and no one machine seems to perform the same. :/

jtara

WebmasterWorld Senior Member jtara us a WebmasterWorld Top Contributor of All Time 5+ Year Member



 
Msg#: 3322469 posted 10:13 pm on Apr 27, 2007 (gmt 0)

Have you installed a specific driver for your monitor, or are you using one of the "generic" drivers? I'd suggest using a specific driver, if one is available. Otherwise, at least make sure you have chosen your monitor from the list of supported monitors. Your video adapter driver may also have a setting to use or ignore DDC.

It sure looks to me like the problem is DDC, since it works fine when you hook-up the monitor directly. The KVM is not sending the DDC to the video adapter.

Global Options:
 top home search open messages active posts  
 

Home / Forums Index / Hardware and OS Related Technologies / Webmaster Hardware
rss feed

All trademarks and copyrights held by respective owners. Member comments are owned by the poster.
Home ¦ Free Tools ¦ Terms of Service ¦ Privacy Policy ¦ Report Problem ¦ About ¦ Library ¦ Newsletter
WebmasterWorld is a Developer Shed Community owned by Jim Boykin.
© Webmaster World 1996-2014 all rights reserved