Quick Answer

To get native uncompressed 4K 240Hz, your GPU must support DisplayPort 2.1a UHBR20, which provides 80 Gbps of raw bandwidth. Connect using a certified UHBR20 cable rated to 80 Gbps and set Windows Display Settings to 4K at 240Hz. RTX 50-series and select RX 9000-series GPUs support this standard natively.

What UHBR20 Actually Means and Why Bandwidth Matters 🔧

DisplayPort 2.1a introduced three bandwidth tiers: UHBR10 (40 Gbps), UHBR13.5 (54 Gbps), and UHBR20 (80 Gbps). Uncompressed 4K at 240Hz with 8-bit colour and no chroma subsampling requires approximately 63 Gbps of payload bandwidth (the actual data after 8b10b or 128b132b encoding overhead). UHBR20 at 77.4 Gbps of usable throughput is the only tier that clears this threshold without requiring Display Stream Compression. Display Stream Compression (DSC) is a visually lossless codec, but native uncompressed output is preferable for colour-sensitive creative work and eliminates any codec-related artefacts on high-contrast OLED panels.

Cables, Ports and Common Setup Mistakes 🎮

The cable is as important as the port. A standard DisplayPort 1.4 cable will physically fit a DisplayPort 2.1a port, but it cannot carry UHBR20 speeds and will cause the system to fall back to a lower link rate, typically capping out at 144Hz or forcing DSC engagement. Use a cable explicitly certified for UHBR20 or 80 Gbps. These cables are shorter by design, typically 1.5m to 2m maximum for passive cables. If you need more than 2m, an active UHBR20 optical cable is required. On the PC side, confirm in the NVIDIA Control Panel or AMD Software that the link rate shows UHBR20 and not HBR3 (the DP 1.4 standard).

GPU Compatibility and the SA Market Context 💡

As of mid-2026, the GPU families with confirmed DisplayPort 2.1a UHBR20 output are the NVIDIA RTX 50-series (5060 Ti and above) and AMD RX 9000-series. RTX 40-series GPUs top out at DisplayPort 1.4 with DSC, which means they can do 4K at 240Hz via DSC but not native uncompressed. For SA buyers, confirmed RTX 5080 or RTX 5090 units stocked at Evetech carry UHBR20 outputs. If your monitor is UHBR20-capable but your GPU is RTX 40-series, DSC 4K 240Hz is your practical option and is visually equivalent for gaming.

TIP

Verify the Link Rate in NVIDIA Control Panel ⚡

After setting up your DisplayPort 2.1a connection, open NVIDIA Control Panel, go to Display and check the link speed shown under the monitor's signal information. It should read UHBR20 if both the cable and GPU support it. If it reads HBR3, your cable is the bottleneck; swap it for a rated UHBR20 cable first before blaming the GPU or monitor.

FAQ

Is Display Stream Compression visually lossless at 4K 240Hz?

DSC is designed to be visually lossless and in the vast majority of gaming scenarios it is indistinguishable from uncompressed output. The compression ratio used at 4K 240Hz is modest, approximately 3:1, which is below the threshold where most people can detect compression artefacts. Native uncompressed output is preferable for professional colour work.

Do any monitors currently sold in SA support DisplayPort 2.1a UHBR20 input?

Yes. Select ASUS ROG, LG UltraGear, and Samsung Odyssey 4K 240Hz monitors released in 2025 and 2026 include DisplayPort 2.1a UHBR20 input ports. Verify the specification sheet for the specific model before purchasing, as some monitors in this resolution and refresh tier include UHBR10 or UHBR13.5 ports rather than UHBR20.

Can I use a USB-C to DisplayPort 2.1a adapter for UHBR20?

Only if your USB-C port outputs DisplayPort 2.1a Alt Mode at UHBR20 speeds. Most current laptop and desktop USB-C implementations are limited to DisplayPort 1.4 or Thunderbolt 4, which tops out at UHBR10 (40 Gbps). Check your GPU or laptop's USB-C specification before expecting full UHBR20 throughput via USB-C.

Looking to max out 4K 240Hz on your PC? Evetech stocks RTX 50-series GPUs and DisplayPort 2.1a-compatible 4K 240Hz monitors. Visit the Evetech GPU and monitor sections to build your high-bandwidth 4K setup.