A video editor reports that after connecting a new 4K UHD monitor to their desktop workstation using an existing cable, the operating system caps the display resolution at 1080p. When the technician attempts to manually force a 4K resolution at 60 Hz, the display flickers briefly and loses signal completely. The graphics card is verified to support 4K output at 120 Hz. Which of the following is the MOST likely cause of this issue?
- The video cable in use lacks adequate bandwidth to support 4K resolution at a 60 Hz refresh rate.Answer
- BThe graphics card VRAM has suffered thermal degradation and cannot render 3D frames.
- CThe display's internal CCFL backlight inverter board is failing to provide required power.
- DThe technician bypassed checking display drivers and must reflash the monitor's BIOS firmware first.
Answer
The video cable in use lacks adequate bandwidth to support 4K resolution at a 60 Hz refresh rate.
Transmitting 4K UHD video at 60 Hz requires a high-bandwidth physical connection (such as HDMI 2.0+ or DisplayPort 1.2+). When a cable lacks the required bandwidth specifications, the display protocol fails to maintain signal integrity at higher pixel clocks, resulting in a black screen, flickering, or the operating system falling back to lower supported resolutions such as 1080p.
Step-by-Step Solution
Key Concept
Video Cable Bandwidth and Resolution Capabilities