DisplayPort 2.1 Explained: UHBR Bandwidth, Cables, and GPUs

DisplayPort 2.1 is VESA's current display standard, and the number on the box matters less than the UHBR tier underneath it: UHBR10 (40Gbps), UHBR13.5 (54Gbps), or UHBR20 (80Gbps). Only the top tier, UHBR20, gets you uncompressed 4K at 240Hz or native 8K at 60Hz, and right now it's standard only on NVIDIA's flagship RTX 5090 and RTX 5080 and a short list of high-end OLED monitors. Here's what the spec actually guarantees, how it stacks up against DisplayPort 1.4 and HDMI, and which cable you need to ask for.

What DisplayPort 2.1 actually is

VESA (the Video Electronics Standards Association) published the DisplayPort 2.1 specification on October 17, 2022. It's easy to assume 2.1 means "faster than 2.0," but that's not what happened here: DisplayPort 2.1 keeps the exact same link rates and bandwidth ceiling as DisplayPort 2.0. The update is about interoperability and certification rigor, not raw speed. VESA's own release notes that the new version is "backward compatible with and supersedes" DisplayPort 2.0, and that every product already certified under 2.0 — GPUs, dock chipsets, monitor scalers, and UHBR cables alike — automatically carries over to the stricter 2.1 spec.

The practical reason VESA made the change was DisplayPort's growing overlap with USB4. DisplayPort 2.1 aligns its physical layer more closely with the USB Type-C and USB4 PHY, which is what lets a single USB4 port tunnel a DisplayPort 2.1 video stream alongside data traffic without the two fighting over the same lanes. That's also why this generation leans so heavily on USB4 2.0's shared-PHY approach and why DisplayPort-over-USB-C has gotten so much more capable in the last few years. A follow-up revision, DisplayPort 2.1a, arrived in January 2024 and added the DP54 cable certification tier, and VESA has continued iterating with DisplayPort 2.1b, which introduces longer active UHBR20 cables (more on that below).

The three UHBR tiers: UHBR10, UHBR13.5, UHBR20

VESA calls DisplayPort's high-speed modes "Ultra-High Bit Rate," or UHBR, to distinguish them from the older HBR/HBR2/HBR3 link rates used by DisplayPort 1.x. All three UHBR tiers use 128b/132b encoding (the same scheme USB4 and Thunderbolt use), which is dramatically more efficient than the 8b/10b encoding DisplayPort 1.4 relies on — about 96.7% efficiency versus roughly 80%. That efficiency gain is why DisplayPort 2.1's effective data rate is so much closer to its raw number than DisplayPort 1.4's is.

A GPU, dock, or monitor that says "DisplayPort 2.1" on the spec sheet doesn't automatically mean UHBR20. Plenty of mainstream and mid-range hardware implements DisplayPort 2.1 at the UHBR10 or UHBR13.5 tier only, which is perfectly spec-compliant but caps out well short of the headline 80Gbps number. Always check which UHBR tier a specific port supports, not just whether it says "2.1."

DisplayPort 2.1 vs. DisplayPort 1.4

DisplayPort 1.4, finalized in 2016, uses HBR3 as its fastest link rate: 8.1Gbps per lane, 32.4Gbps raw across four lanes, and about 25.92Gbps of effective throughput after 8b/10b encoding overhead. DisplayPort 1.4 can still drive 4K at 120Hz or even 8K at 30Hz, but only by leaning on Display Stream Compression (DSC), a visually lossless compression scheme that's mandatory for anything beyond roughly 4K 60Hz HDR on that link rate.

Even DisplayPort 2.1's lowest tier, UHBR10, already beats DisplayPort 1.4's raw bandwidth by about 24%, and UHBR20 more than doubles it. The practical difference shows up most at high refresh rates: DisplayPort 1.4 needs DSC for 4K above about 120Hz, while UHBR20 can push 4K at 240Hz with zero compression at all. DSC itself hasn't gone away on DisplayPort 2.1 — VESA's spec materials put its compression ratio at better than 3:1 — it's just no longer mandatory for the resolutions and refresh rates most gaming monitors target today.

DisplayPort 2.1 vs. HDMI 2.1 and HDMI 2.2

HDMI's most recent widely deployed standard, HDMI 2.1, tops out at 48Gbps of raw bandwidth over its Fixed Rate Link (FRL) — comfortably ahead of DisplayPort 1.4, but still well short of DisplayPort 2.1's UHBR20 ceiling. The HDMI Forum has since moved the goalposts again with HDMI 2.2, which doubles the FRL ceiling to 96Gbps across new "Ultra96" tiers of 64, 80, and 96Gbps; see our HDMI 2.2 explainer for how that standard's tiers break down and when certified cables actually started shipping.

In short: DisplayPort 2.1 at UHBR20 currently out-bandwidths standard HDMI 2.1, but HDMI 2.2's top tier leapfrogs it again on paper. In practice, which one matters to you depends entirely on your GPU and monitor — PC gaming monitors have standardized almost entirely on DisplayPort for their highest refresh-rate modes, while HDMI remains the default for TVs and consoles.

What resolutions and refresh rates DisplayPort 2.1 actually enables

The resolution and refresh-rate combinations a given DisplayPort 2.1 link can drive depend entirely on which UHBR tier it implements, and on whether DSC is in play:

• UHBR10 (40Gbps): 4K at 60Hz with HDR and no compression, or 4K at up to 120Hz+ with DSC.
• UHBR13.5 (54Gbps): 4K at 120Hz HDR without DSC, or up to 4K 240Hz-class refresh rates with DSC.
• UHBR20 (80Gbps): 4K at 240Hz with full 10-bit HDR and zero compression, or 8K at 60Hz with DSC.

That UHBR20-without-DSC math is tight by design: a 3840×2160 signal at 240Hz with 10-bit color sits right around the 80Gbps raw ceiling, which is exactly why VESA pitched UHBR20 as the tier for native, compression-free 4K 240Hz gaming. Anything beyond that — 8K at high refresh, or multiple 4K displays daisy-chained off one port — still needs DSC even on the fastest tier.

Which GPUs support DisplayPort 2.1 today

GPU support for DisplayPort 2.1 is still split by UHBR tier, not just by the "2.1" label:

• NVIDIA RTX 50-series (Blackwell): NVIDIA's own RTX 5090 product page lists three DisplayPort 2.1b outputs with full UHBR20 support, alongside one HDMI 2.1b port, enabling "4K at 480Hz or 8K at 165Hz with DSC" according to NVIDIA. The RTX 5080 shares the same UHBR20-capable display outputs; lower-tier RTX 50-series cards may implement a lower UHBR tier, so it's worth checking the spec sheet for a specific board.
• AMD Radeon RX 9000-series (RDNA 4): AMD's RX 9070 and RX 9070 XT ship with DisplayPort 2.1a and HDMI 2.1b outputs. Board-partner spec sheets and retailer listings for RDNA 4 cards consistently describe the DisplayPort implementation as topping out at UHBR13.5 (54Gbps) rather than the full UHBR20 — enough for 4K at 120Hz HDR without compression, but short of native 4K 240Hz.

If you're not sure what's already in your PC, checking your exact GPU model is the first step before looking up its specific DisplayPort tier. And if you're pricing out a UHBR20-capable card, our RTX 5090 pricing roundup has where street prices actually stand right now.

Which monitors support DisplayPort 2.1 UHBR20

UHBR20 monitors are still a premium-tier feature rather than something you'll find on a budget 4K display. ASUS's ROG Swift OLED PG27UCDM — a 27-inch (26.5-inch viewable) 4K QD-OLED gaming monitor at 240Hz — is one confirmed example: its official spec page lists a DisplayPort 2.1 input with a bundled DP80 cable, meaning the port is certified for the full UHBR20 link rate. That pairing (DisplayPort 2.1 input plus an included DP80 cable) is becoming the template other high-end 2025-2026 QD-OLED and OLED gaming monitors are following as 4K 240Hz panels become more common, though exact UHBR tier still varies by model and it's worth confirming on each monitor's own spec sheet rather than assuming from the "DisplayPort 2.1" label alone.

Lower-tier monitors — including plenty of perfectly good 1440p 144Hz-240Hz displays — may list "DisplayPort 2.1" while only implementing UHBR10 or UHBR13.5, since those tiers are already enough bandwidth for their resolution and refresh rate. That's not false advertising, it's just the same "check the tier, not just the version number" rule that applies to GPUs.

What cable you actually need

VESA's certification program labels cables by the UHBR tier they're guaranteed to carry, not by "DisplayPort 2.1" generically:

• DP40 cables are certified for UHBR10 (40Gbps), and come in full-size DisplayPort, Mini DisplayPort, and USB-C form factors.
• DP54 cables, added with the DisplayPort 2.1a update, are certified specifically for UHBR13.5 (54Gbps).
• DP80 cables are certified for the full UHBR20 link rate (80Gbps) and also cover UHBR13.5.

One real limitation: VESA-certified passive DP80 cables are only guaranteed at UHBR20 up to about one meter. For longer runs, VESA has been developing DP80LL ("low loss") active cables, announced as a highlight of DisplayPort 2.1b, which push certified UHBR20 runs out to roughly three meters. VESA compliance program manager James Choate said the goal is that "users are no longer limited to a one-meter cable connection between their DisplayPort 2.1 UHBR20 source and hub or sink devices." If your desk setup needs more than a meter of cable between a UHBR20 GPU and monitor, check specifically for DP80LL or another active, VESA-certified option rather than grabbing any cable labeled "DisplayPort 2.1."

The good news for anyone who bought cables during the DisplayPort 2.0 era: VESA has stated that existing certified DP40 and DP80 cables carry their certification straight over to DisplayPort 2.1 without needing new hardware.

DisplayPort 2.1, USB4, and Thunderbolt

Because DisplayPort 2.1 shares its physical layer with USB4, UHBR video increasingly travels over USB-C ports rather than dedicated full-size DisplayPort connectors — especially on laptops and docking stations. Thunderbolt 5's 80Gbps (and burst-mode 120Gbps) links are built to tunnel DisplayPort 2.1 UHBR streams alongside data and power on a single cable. In practice, that means a modern USB4 or Thunderbolt 5 dock can carry a full UHBR20 signal to an external monitor, but only if every link in the chain — the host port, the cable, and the dock — is actually certified for that tier. A generic USB-C cable that happens to carry a video signal is not the same thing as a certified DP80 or Thunderbolt 5 cable.

What's next for DisplayPort

DisplayPort 2.1 isn't the end of the roadmap. VESA has continued shipping incremental updates — DisplayPort 2.1a added the DP54 cable tier, and DisplayPort 2.1b is bringing longer, active UHBR20 cabling through the DP80LL spec. None of these revisions change the underlying UHBR10/13.5/20 bandwidth ceiling; they're about making the existing tiers easier to certify, cable, and deploy reliably. For now, the practical story for anyone shopping GPUs or monitors is unchanged: look past the "DisplayPort 2.1" label on the box and confirm the specific UHBR tier and cable certification before assuming you're getting 4K 240Hz without compression.

Written byMara Lindqvist

Mara Lindqvist edits the hardware desk. She covers graphics cards, processors, memory and storage, the foundries and chip designers behind them, and what the numbers on a spec sheet mean for people choosing a PC. Specifications in her stories come from manufacturer spec pages and datasheets.

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