DisplayPort UHBR10 vs UHBR13.5 vs UHBR20 Bandwidth

The Ultra-High Bit Rate (UHBR) transmission modes introduced in the DisplayPort 2.0 and 2.1 specifications significantly increase bandwidth compared to older standards. This article compares the raw gigabit-per-second (Gbps) throughput and effective data payloads of UHBR10, UHBR13.5, and UHBR20 across standard four-lane DisplayPort connections.

The Underlying Transmission Architecture

All DisplayPort UHBR tiers utilize a 4-lane physical connection and the 128b/132b line coding scheme. Older DisplayPort standards (such as HBR3) used an 8b/10b encoding system, which incurred a 20% transmission overhead. The 128b/132b encoding reduces overhead to approximately 3.03%, allowing roughly 96.97% of the raw physical signaling rate to carry actual display data.

UHBR10: Entry-Level Ultra-High Bit Rate

UHBR10 delivers a raw physical signaling rate of 10.0 Gbps per lane.

• Raw Bandwidth (4 Lanes): 40.0 Gbps
• Effective Data Payload: 38.69 Gbps

With a 40 Gbps raw ceiling, UHBR10 provides nearly a 23% raw bandwidth increase over DisplayPort 1.4a’s HBR3 limit (32.4 Gbps). Because of the more efficient 128b/132b encoding, the effective payload jump is even higher—delivering roughly 49% more usable data than HBR3's 25.92 Gbps payload limit. UHBR10 can drive uncompressed 4K displays at refresh rates up to 144 Hz or 8K displays using Display Stream Compression (DSC).

UHBR13.5: Mid-Tier Ultra-High Bit Rate

UHBR13.5 scales the per-lane signaling rate to 13.5 Gbps.

• Raw Bandwidth (4 Lanes): 54.0 Gbps
• Effective Data Payload: 52.22 Gbps

UHBR13.5 represents a 35% increase in throughput over UHBR10. This tier is often targeted at high-end consumer hardware, docks, and laptops, balancing signal integrity constraints with high-speed performance. A 54 Gbps raw pipe allows for uncompressed 4K at 240 Hz (8-bit or 10-bit color depending on timing) and enables multi-monitor 4K setups over a single cable without visual compression.

UHBR20: Maximum DisplayPort Performance

UHBR20 represents the maximum throughput specification available under DisplayPort 2.1, pushing signaling to 20.0 Gbps per lane.

• Raw Bandwidth (4 Lanes): 80.0 Gbps
• Effective Data Payload: 77.37 Gbps

UHBR20 doubles the raw bandwidth of UHBR10 and provides a 48% increase over UHBR13.5. At 80 Gbps raw, it is the fastest single-cable video interface currently available in consumer electronics, surpassing HDMI 2.1's 48 Gbps ceiling. This bandwidth supports an uncompressed 8K display at 60 Hz with 10-bit HDR, dual 4K displays at 144 Hz uncompressed, or extreme refresh rates such as 4K at 480 Hz when utilizing DSC.

Side-by-Side Performance Comparison