I found my answer with similar laptop specs from HP and Lenovo. The T1200 does not support HDMI 2.1. Telling people that Precision 7560 supports HDMI 2.1 is a lie.
Hello,   I have a TV LC C9 supporting HDMI 2.1 and is able to display 4k at 120hz. It works well with my personal desktop with a NVIDIA 3060Ti. I received a professional laptop, a Precision 7560, with a NVIDIA T1200. I disabled the Hybrid mode to be able to have the best I can have on the HDMI port, according to this sheet: [URL]   Unfortunately, I still cannot display my monitor in 4K 120hz, as you can see in the following screenshot: [IMAGE]   Do I need to do something else?
Precision 7560 really HDMI 2.1?