KVM blues

The KVM switch arrived today. (That was fast!)

I hooked it up and things are a bit dodgy. I have three PCs attached: a Dell Dimension 2350, a Dell GX240, and a SystemMax 765. The Dimension 2350, running SuSE Linux 11.1, works without problems. The GX240 should work -- I have yet to test it -- but when turned off it prevents the KVM switch from working. (It did this to another KVM switch too, so I know the problem is the Dell.)

The SystemMax 765 has odd behavior. The keyboard and mouse don't work... most of the time. Sometimes they do, for a short while. Sometimes the mouse works but not the keyboard. I don't see a pattern. It might be the cable, or the KVM switch, or the SystemMax CPU board (specifically the PS/2 ports) or it might be Windows 7(RC). Or possibly the mouse -- some KVM switch/mouse combinations do not get along. Or maybe the KVM switch needs an external power supply.

I don't think I have a spare PS/2 mouse. Or a power supply for the KVM switch. (It does not come with one.)

Another puzzle to solve!