I've been searching and googling on this and have not found any real fixes for my issue. I know the root cause of this is the KVM I am using and I have no way of replacing it so I must make it work. This is also an issue at work where I work in a lab doing testing with Linux and Windows. Windows machines do not have any issues with this. I also use both 32 and 64 bit versions.

I am using both Red Hat Ent. Linux 4 Update 3 and Suse Linux Ent Linux 9.3 and am having the same issue with both. The relevance here is that they each use different versions of X. They both have the same issue though.

When I connect my machines to the KVM, I get a real resolution of about 640x480. Anything I try above this gets a virtual resolution. When I connect the monitor directly to the machine it works correctly. With RedHat, I have saved the xorg.conf file when connected to the KVM and compared this to the xorg.conf file when it is directly connected to the KVM and there is no difference in the file. No virtual resolutions are setup for either distro. I have tried changing the modelines and the refresh rates with no success.

Does anyone have any ideas that may work with this? I do not know what refresh rates the KVM supports as it is an old one and the numbers are not posted anywhere that I have been able to find. The KVM is an Apex (Now Avocent) EL-480DT.

I do need to add that if I start X with the monitor directly attached and switch it to the KVM, it works fine until I restart X or reboot.

This is definitely in the way that X does it autoconfigure so something here is not autodetecting or autoconfiguring correctly so I need to do this manually. Is there anyone that can give me more info on the modelines or somthing to point me in the right direction?

I still need advice on how to procede on this as this is a major issue. Any advice would be very welcome.