I just got my order for the 4-port DisplayPort 1.4 KVM (model PAAG-E3124B) that I purchased through LevelOneTechs, and to my utter astonishment, unlike all of the other KVMs I tried, I was able to swap out my old StartTech DP 1.2 switch (which my new gaming rig didn’t work well with) and plugged the new DP 1.4 KVM in and everything worked the first time…with one mystifying gotcha:
Switching between everything works great, EXCEPT if I switch directly from the Apple Silicon Mac Mini on port 2 to either of the Windows-based PCs (ports 1 and 3). If I switch directly from the Mac Mini to either PC, the PCs (which normally run at 4K resolution and 120/60hz, respectively) will drop back to 640x480 resolution. My workaround for this is to switch to the Intel-based MacBook Pro and then back to either of the PCs, which will then show up in the proper 4K resolution. Very odd.
Here’s what I have hooked up to the KVM:
Intel i9-13900K Z790 chipset gaming rig with an RTX 4090 GPU, connected via a FIBBR brand fiber optic DisplayPort cable
2020 Mac Mini M1 that’s putting out video via a StarTech Thunderbolt-to-DisplayPort cable
An old Intel i7-4790K Windows 10 machine with a GTX 1080 GPU, connected via a FIBBR-brand fiber optic DP cable
My work laptop, which is a 2020 Intel i7 Macbook Pro, connected with a single cable to an OWC ThunderDock and from there to the KVM with a Thunderbolt-to-DP cable
The KVM is connected to a 32" ASUS P32UQR 4K 144hz monitor with the DP 1.4 cable that came with the monitor.
this is poisoning the well. It detects the display is gone and resets the resolution to 640x480. If you pull it from the equation, reboot everything then retry the windows switching you’ll find it doesn’t go to 640x480.
Need a better usbc to DP cable. It’s because there’s “smarts” in those kinds of cable (that, in this case, not very smart). We usually recommend moshi brand cables.
GTX 1080 GPU,
You may need to google nvidia dp1.4 firmware update and update your 10 series GPU. It thinks it supports DP1.4 but it doesn’t really. the firmware update mostly fixes it.
Based on a hunch that the video out of the Apple Silicon Mini was doing something weird, I yanked the StarTech Thunderbolt-to-DP cable that was connected directly to the back of the Mac Mini, and replaced it with another of the cheap-o Amazon Basics Thunderbolt-to-DP cables that I’m using with the Intel-based MacBook Pro. But instead of plugging it directly into my Mac Mini, I plugged it into an identical OWC Thunderbolt dock on the M1 Mac Mini that had a free TB port. And Bob’s your uncle - I can now switch between all of the machines in my mongrel KVM setup without the resolution dropping.
Kudos on selling the first DP 1.4 KVM that actually seems to work properly!
The only thing that would make this perfect is if it had EDID display emulation built into it*, but I can live with the windows shifting around a bit if it gives me the convenience of hotkey-switching between my gaming rig and my “getting stuff done” computers.
Thanks!
Scott
if you guys sell an EDID emulator gadget that would work in my setup, please let me know
Ah yes. It’s actually more of an issue with my work Macbook, although having the windows switch over to the laptop display when I switch to another machine actually comes in handy (I can keep an eye on builds at work while I switch away to do other things).
