DisplayPort 2.1 vs. HDMI 2.1: The Definitive Bandwidth Chart for 2026
Key Takeaway
- The Bandwidth King: DisplayPort 2.1 (specifically the UHBR20 tier) offers a massive 80 Gbps of bandwidth, nearly double the 48 Gbps offered by HDMI 2.1.
- Uncompressed 4K 240Hz: DP 2.1 is the only cable standard capable of running a 4K monitor at 240Hz with 10-bit color without relying on Display Stream Compression (DSC).
- The DP 2.1 Confusion: Not all DP 2.1 ports are equal. They are divided into three tiers: UHBR10 (40 Gbps), UHBR13.5 (54 Gbps), and UHBR20 (80 Gbps). You must check your GPU and monitor specs carefully.
- Cable Length Limits: To achieve the full 80 Gbps of UHBR20, passive copper cables must be extremely short (usually under 1 meter). Longer runs require expensive active optical cables.
If you buy a cutting-edge 4K 240Hz or 8K 60Hz monitor in 2026, the biggest bottleneck isn't your GPU's rendering power—it's the physical cable connecting the GPU to the screen. For years, HDMI 2.1 and DisplayPort 1.4 have relied on compression algorithms to squeeze high-refresh-rate signals through limited pipes. But with the widespread adoption of DisplayPort 2.1, the bandwidth floodgates have opened. Here is the definitive breakdown of DP 2.1 vs. HDMI 2.1.
The Raw Bandwidth Numbers
To understand the difference, we have to look at the maximum data rate each standard can handle.
- DisplayPort 1.4: 32.4 Gbps (25.9 Gbps usable data rate)
- HDMI 2.1: 48.0 Gbps (42.6 Gbps usable data rate)
- DisplayPort 2.1 (UHBR20): 80.0 Gbps (77.4 Gbps usable data rate)
As you can see, the top tier of DisplayPort 2.1 offers nearly double the usable bandwidth of HDMI 2.1. This massive pipe changes how monitors handle high resolutions.
The Death of Compression (DSC)
To run a 4K monitor at 240Hz with 10-bit HDR color, you need roughly 68 Gbps of bandwidth. Because HDMI 2.1 maxes out at 48 Gbps, it is physically impossible to send that signal uncompressed. The monitor and GPU must use Display Stream Compression (DSC) to shrink the data.
While DSC is "visually lossless," it has drawbacks. Enabling DSC often disables features like NVIDIA DSR (Dynamic Super Resolution) or custom resolutions, and it can occasionally cause alt-tabbing black screens. DisplayPort 2.1 (UHBR20) has 77.4 Gbps of usable bandwidth. This means it can run 4K 240Hz completely uncompressed, bypassing the DSC engine entirely.
The DP 2.1 Tier Trap
The biggest issue with DisplayPort 2.1 is that VESA (the governing body) allowed manufacturers to label their ports as "DP 2.1" even if they don't support the maximum speed. There are three tiers of DP 2.1:
- UHBR10 (40 Gbps): Actually slower than HDMI 2.1.
- UHBR13.5 (54 Gbps): Slightly faster than HDMI 2.1.
- UHBR20 (80 Gbps): The true next-gen standard.
When buying a DP 2.1 monitor or GPU, you must dig into the spec sheet to ensure it specifically supports UHBR20.
Frequently Asked Questions
Do I need a new cable for DisplayPort 2.1?
Yes. To achieve UHBR20 speeds, you must buy a VESA-certified "DP40" or "DP80" cable. Older DP 1.4 cables will not have the shielding required for 80 Gbps.
Does HDMI 2.1 support 8K?
Yes, but only at 60Hz, and it requires heavy use of Display Stream Compression (DSC) to fit the signal into its 48 Gbps limit.
Which is better for a TV: HDMI or DisplayPort?
HDMI 2.1 remains the undisputed king of the living room. Almost no consumer televisions feature DisplayPort inputs, and HDMI features like eARC (for soundbars) make it superior for home theater setups.
Can I adapt DP 2.1 to HDMI 2.1?
Active adapters exist, but they are expensive and often introduce latency or break VRR (Variable Refresh Rate) support. It is always best to use a native connection.
Why are DP80 cables so short?
Pushing 80 Gbps through copper wire creates massive signal degradation. Passive DP80 cables are usually limited to 1 meter (3.3 feet). For longer runs, you need expensive fiber-optic active cables.
How can I check if my cable is bottlenecking my refresh rate?
If you set your monitor to 240Hz but it keeps reverting to 120Hz, your cable might be the bottleneck. You can verify your active refresh rate using our tool below.
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