Dell UltraSharp 34 Curved Monitor - Manual (Page 43)

Operating the Monitor | 43
Input Color
Format
Allows you to set the video input mode to:
RGB: Select this option if your monitor is connected to a computer (or
DVD player) using the HDMI cable (or DisplayPort cable); or MHL
devices using MHL cable.
YPbPr: Select this option if your monitor is connected to a DVD player
by YPbPr using HDMI cable (or DisplayPort cable); or MHL devices by
YPbPr using MHL cable.
Or if the DVD (or MHL devices) color output setting is not RGB.
Gamma Allows you to set the Gamma to PC or MAC.