I don't notice it when using it for work. I barely notice it when using it for console games. Probably wouldn't want to use it for competitive shooters, but non-issue for most other games.
Few more notes:
- I use PCIE rather than USB for the capture card
- Can be costly if you need 4k + multiple inputs (for multiple "monitors" as different OBS windows)
- I had issues getting the capture card to recognize scaled HiDPI resolutions from my work Mac
You can do this without a capture card using https://ndi.tv/tools/ - other clients on your LAN can view in OBS or with the included program. I'm yet to try it with 4k.
No help with consoles of course, and perhaps not an option for a work machine.
edit: feature list also mentions "KVM remote control of any workstation running Scan Converter from NDI Studio Monitor"
I use NDI a lot, but with a phone as webcam, or from obs to obs, scan converter, audio stream between devices like ipad/iphone/Android to desktop... But it is demanding to encode this way. HDMI capture does only use bandwidth over the USB or pcie bus, while ndi uses cpu or gpu.
HDMI capture cards can definitely use CPU, and this is the case for most USB capture cards as USB does not have enough bandwidth to send an entire raw stream in realtime.
Few more notes:
- I use PCIE rather than USB for the capture card
- Can be costly if you need 4k + multiple inputs (for multiple "monitors" as different OBS windows)
- I had issues getting the capture card to recognize scaled HiDPI resolutions from my work Mac