Bought a KVM switch, everything seems fine. I am using Windows 7 with a DVI expansion card. I connected the cables to the main ports of the KVM switch and tried using the first port to connect to the computer. I got no response, no video movement, no keyboard, no mouse. The light on the keyboard and mouse was on, meaning power was going to them. So I gave it about 10 minutes, maybe there was a hidden hard drive that needed to be installed. However, there is no response, so I select port 3 on the KVM switch, mouse movement across the screen was sporadic making operation difficult, and the keyboard was unresponsive. I tried plugging the USB keyboard and mouse into a different port, thinking I had a bad USB port on my computer, but no luck. I tried using a KVM switch on another Windows 7 computer with a different expansion card. I got the same result (port 1 - no video, no keyboard or mouse, ports 2-4 - mouse movement sporadic, no keyboard) so at this point I think I just got a bad block. I ask for block replacement. When the replacement KVM switch arrived, I went as far as buying a new cable. Everything connected to the appropriate port, but still no picture, and the moment with the mouse was sporadic. I bought one of the old KVM switches I bought a few years ago and everything seems to be working fine. The video mouse keyboard works on a computer. On port 4 I was finally able to get the picture.
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