How to set up dual monitors, 2 computers (1 Mac Mini M2, 1 PC), and shared peripherals using a KVM switch?

That first part is absolutely correct. I've seen maybe 1 KVM that has a USB-C, but then, is it going to work with the TB4 cable coming from the Mac Mini? I don't know? The one I saw on Amazon said something like: Macs don't allow two monitors or something like that. So who knows if it even works?

Then, is that ALL it takes?! Is one adaptor and this whole thing might work? Are you 99-100% sure that will work? If so, man, that's fantastic news!

So here's one I found that has Computer 1 using Dual HDMI and 1 USB port, while Computer 2 uses 1 USB-C port. They always list this is a "laptop" for some reason? But I'm wondering if this would work for what I want to do?

My other question is in regards to the TB4 cords/ports. For regular PCs and KVMs, you HAVE to have either 2 HDMI and 1 USB or 1 HDMI, 1 Display Port and 1 USB to go from the PC to the KVM for it to work with dual monitors and 1 set of peripherals. But what about TB4? Does the 1 cable do all that? Meaning, all you need to do is hook up 1 TB4 cable to the back of the Mac Mini, then plug that into the KVM and it all works? Or do I need to use that TB4 to HDMI adapter you showed? I'm not following that part.

Then on to the next section. I'm not sure what KVM's you're referring too, but all the videos I've seen of dual monitor KVMs do allow you to do both options. Meaning, they allow you to either have Monitor 1 show CPU 1 and Monitor 2 show CPU 2 or Monitor 1 and 2 show CPU 1 or Monitor 1 and 2 show CPU 2. One of those TESmart KVM's has a remote and you just press one of the buttons to toggle between 1 monitor or both. This is the photo from the KVM I linked above, showing how you can do what I just said. And this one isn't even a "great" one or top of the line.

H = HDMI

DP = Display Port

So this is a crude little diagram I drew to show what I "think" might work if Plan A doesn't. I made this drawing a few days ago, after I had been posting for help and searching endlessly for KVM switches that would do what I want and realizing it may just not work. And now it sounds like you're saying it won't. So my plan B was what I "think" you might be talking about?

The Mac Mini just has 1 cable going straight to monitor 2. Never using any other monitor except monitor 2. And then I'd also hook the Mac Mini up to the KVM switch so I can use the mouse and keyboard and speakers.

Then have the PC using the KVM as normal. So DP, HDMI and USB cords going from the computer to the KVM. Then a DP or HDMI from the KVM to Monitor 1 and 2, so that the PC can use both screens. While the Mac only is on one screen. Would that work? Is this what you're suggesting? Or something else?

If I can at least use the mouse, keyboard and speakers between the two computers and then just use one monitor for the Mac, I would be fine. Not ideal, but fine.

While I appreciate that advice, my dream setup does not consist of Logitech keyboards and mice that pair through BT or whatever. I have a very expensive custom built keyboard I made that uses a USB-C cable.

I have read of this idea of switching monitors through the OSD menu, but not sure how that works? And if I have to get into a menu by futzing around with the monitor button that is almost always hidden or on the back of the computer, then find the input menu and switch it, that's too much time and work. I just want to be able to press 1 button and have it all switch over seamlessly. But if you can explain how it works in detail, I would appreciate that since I'm not following how this would work.

That depends on the Mac in question. Macs these days support up to 6 displays and the M2 Mac mini supports up to 3 Displays if using the M2 Pro CPU. So that should not be an issue. Their description was likely written with the M1 variations in mind which only supported 1 external display, but even M1 Mac mini supported 2 since it has no built in screen of its own.

So the Mac Mini I'm going to be purchasing is a regular M2, not the pro. But I looked it up and it says it supports up to 2 displays, so I should be good there. And good to know what they mean is the M1 variations won't work. I think I remember seeing something about M1 in the photos for the product.

The TB4 port and cable can transmit video and data, and if the KVM supports data from the USB-C port in addition it video it should work. If its only expecting video, the other ports for keyboard and mouse may require an additional cable.

The TB4 to HDMI adapter is just a suggestion if using a KVM that does not support USB-C input and only has HDMI ports. If the KVM like the one you show has USB-C input from the computer, you don't really need the HDMI adapter. The adapter was just for KVMs that don't offer USB-C.

Also of note, is if the KVM supports Thunderbolt signals, DisplayPort signals or just video over USB-C. Generally the Mac can negotiate that automatically but may or may not cause an issue with the KVM.

Ok, that's also very helpful information to know. I had no idea that a TB4 cable/port transmits/receives video, audio and data all in one. That's amazing! And I see what you're saying now about the USB-C KVM or the adapter. I'd only need the adapter if I CAN'T find a KVM that has one of the computer inputs as USB-C. So I'll first just try to find a KVM that does everything I want and one of the computer inputs is USB-C. That would be simpler. But as you said, if not, I can just use the HDMI to USB-C adapter. As for the last part, I'm not sure I follow completely, but I think that would just be down to buying it, trying it and seeing if it works or not. As long as I do this through Amazon, it'll be super easy to buy and return anything that doesn't work and move on to another one.

Thank you for all of this. I'm not still not feeling like I 100% understand what I need to find or how it all works perfectly, but I'm getting a much better picture after these few posts. I need to start sifting through all the KVM switches on Amazon and see which ones have everything I need and want and then just buy one and see if it works.

Ok, so I did a bit more research and found out what some of these KVMs meant when they said Mac doesn't do multiple monitors or something to that effect. It's not that they don't support multiple monitors. It's that Macs don't support MST and instead are SST. So multi-stream support vs single-stream support. So Mac's can't support MST, which means the USB-C TB4 port/cable it uses can't support extended display mode. So you can't have one giant screen on two monitors, only copies. And that is NOT what I want. So I'm not even sure a really good KVM that has a USB-C port for one of the Computer inputs will even work? I'm really not finding anyone that knows here or any other PC forums, so I guess I'll have to try and find some time to drive to a Microcenter or some place like that and see if they know. This is really frustrating.

And when I search through all the KVMs on amazon, the reviews are SOOOO all over the place. It's ridiculous. One review will say it's the best thing ever and works flawlessly, then the next says it does nothing it's supposed too, doesn't work with my computer, flickers, doesn't switch over, won't support extended mode, yada yada yada. Just a laundry list of things it WON'T do. So even when I find one that looks like it "might" work, the reviews are so awful, I don't even want to waste my time. It's just crazy how little good information there is on this topic and that nobody knows how to do this on any of the forums. Not your fault and not blaming you. I appreciate you trying to help for sure. I've gotten more help and info from your two posts than anyone else. Just saying in general, I'm still really not that much closer to making this happen then when I started and that is really frustrating.

At this point, I don't really care about two monitors for my Mac Mini. One is fine. Especially if it makes this whole setup work. The PC is really the only computer I really would like and need to have two monitors.

So if that is the case, and I only need the Mac Mini with 1 monitor, is my original drawing/diagram correct?

And follow up, what would I need to hook the Mac Mini up to the KVM so that I can have the keyboard, mouse and speakers work with the Mac and the PC. Do I need some sort of simple docking station or something else? Not sure how that part would work.

Thank you

Yeah, I mean originally I DID want to have both computers able to use both monitors in extended mode or have one computer on each monitor. But after reading up on this, doing research and comments on forums here (yours specifically) and a few others, I've come to the realization that it probably or isn't going to work exactly how I want. And I was just saying, I'm fine if the Mac is only able to work on one of the screens, as long as the PC can be on both. Just so I can get this to work. It'll be close enough to perfect.

Thanks again for the info and help. I'll have to make a reminder in my iphone to come back here and post my finished setup, so you can see what you helped me accomplish. I've been wanting to do this for years and finally said to myself: "lets just do it. Let's go crazy and make a fantastic setup." So I'm doing it, but this KVM switch thing has been stopping me from starting, because I didn't want to buy anything until I knew what I could do or not do. And didn't want to buy anything that may not work out. And now I know. So now I just have to buy a few things and put it all together.

Best