Thanks to all who replied! Everybody had good points. I ended up putting the unit on the non-battery side of the UPS (just because I was out of outlets on the battery side and didn't want to take the time / space to add a powerstrip or such (space is tight behind / under my desk)). I usually feel that the surge suppression there is better than on some inexpensive powerstrips.
In the course of plugging in a power supply for a laptop (which was the reason to switch from a 2-port KVM to a 4-port KVM), I accidentally tripped the power to the KVM switch with no ill effects, that is, the computer did not lose its communication to the monitor, keyboard, and mouse, and, after I repowered the KVM, I could switch between the computers as before the power loss, so I'm not worried about not being on the UPS. I did learn some things (one mentioned above), another is: * the KVM has inputs for either a PS/2 keyboard and mouse, or a USB keyboard and mouse. My mouse is USB and my keyboard is PS/2. I found that if I plugged the keyboard into the PS/2 port and the mouse into a USB port, that would not work for the most finicky computer. I added a USB to PS/2 converter plug to the mouse, plugged them both into USB ports on the KVM, and now things worked. * the output from the KVM (to the computer) has one USB cable and one PS/2 cable. After I did the above, I was able to plug the PS/2 cable into the keyboard port on the computer, and the USB cable into a USB plug, and the mouse and keyboard both worked. (I thought I might have to add another USB to PS/2 converter plug so that I could plug both cables into the PS/2 ports on the computer. * The other (desktop) computer I consider less finicky. (Because, when I tried to set it up with the inexpensive 4-port all USB KVM that I bought on ebay, it worked with no trouble, the finicky computer would not, even when I used things like a cable splitter and USB to PS/2 converter plugs) to plug into either both PS/2 "jacks" or two USB ports on the computer (or the various possible combinations of one each)) Anyway, this less finicky computer has only one PS/2 ports, colored half pink and half gray, and apparently can work for either a PS/2 mouse or a PS/2 keyboard (or maybe even both with some kind of "combiner cable"). I ended up plugging the PS/2 cable from the KVM into the PS/2 port on the computer and the USB cable into a USB port, and both the mouse and keyboard work. I didn't try any other approaches, I mean, I didn't try to see if only one of the KVM output cables connected to the computer would be sufficient. I am just a little worried that maybe the mouse and keyboard signals are going into both the PS/2 port and a USB port, and that maybe someday I'll encounter some kind of problem because of that, but, for now I'm happy that everything (on these two computers) seems to be working ok through the KVM. I do have another OT problem related to the laptop and the existing installation of Windows on it. I'll describe that problem later (in a new thread) to see if anyone can help. Thanks again to the list and those who replied! On Thursday, January 30, 2020 08:36:32 AM Roger Price wrote: > Speaking from experience, another reason to put the KVM switch on the UPS > is protection from power surges. I live in a lightning prone area, and I > have lost expensive gear because ancilliary stuff such as a KVM switch > with a wired connection to PCs was not protected.
