DisplayPort 2.1 became a much bigger talking point than expected when AMD revealed its upcoming RX 7900 XTX and RX 7900 XT GPUs. It is the latest DisplayPort standard, specification revision 2.0, released in 2019, and is a natural inclusion for next-generation GPUs. There’s just one problem – Nvidia’s behemoth RTX 4090 still uses DisplayPort 1.4a.
While the 1.4a spec is still more than enough for most people, the inclusion of DisplayPort 2.1 gives AMD the edge this generation. No, I’m not here to sell you 8K gaming—in some parts of the world, 8K may not even be possible—but for a lot of competitive gamers and VR enthusiasts, DisplayPort 2.1 could be a big shift.
The update was four years in the making
VESA, the company that defines and certifies the DisplayPort standard, released DisplayPort 2.1 in October 2022. It usually takes years for products to make it to market that support a new standard, but DisplayPort 2.1 isn’t that new. It’s a refresh of DisplayPort 2.0, which was introduced in 2019, and a huge improvement over DisplayPort 1.4, which we’ve been seeing since 2016.
As with any new connection, bandwidth is important. DisplayPort 1.4a, which you’ll find on all newer graphics cards except the Intel Arc A770 and A750 and AMD’s upcoming RX 7900 XTX, reaches a maximum data transfer rate of 25.92 Gbps. DisplayPort 2.1 reaches up to 77.37 Gbps (theoretical bandwidth is higher if you see different numbers, but this is the actual data transfer rate possible over the cable). If you do some really complicated math, you’ll find that the required data rate for 4K at 120Hz with HDR on is 32.27 Gbps – more than DisplayPort 1.4a is capable of.
Monitors like the Samsung Odyssey Neo G8 only support 4K at 240Hz with DisplayPort 1.4a, so what does that mean? DisplayPort (and now HDMI) uses Display Stream Compression (DSC) to reduce the amount of data required. DSC is not mathematically lossless, but it is visually lossless. It can reduce the required data by up to a 3:1 ratio, reducing the 32.27 Gbps figure all the way down to 10.76 Gbps. It’s great, and DSC is the only reason DisplayPort 1.4a hasn’t been kicked to the curb yet.
The problem is that DisplayPort 1.4a limitations are starting to appear, even with DSC enabled. A theoretical 4K monitor at 360Hz wouldn’t be able to run at full refresh rate, even with 3:1 DSC compression (the claimed data rate is 36.54 Gbps, in case you were wondering). And higher color depths for HDR add even more bandwidth requirements, as well as higher refresh rates and resolutions.
A 4K 360Hz monitor might sound crazy now, but we have hardware that can drive such a display. AMD claims 295 fps at 4K and Apex Legends and 355 frames per second Overwatch 2. In addition, the RTX 4090 can accelerate above 300 frames per second at 4K and Rainbow Six Siege, and the frame-rendering capabilities of DLSS 3 and the upcoming FSR 3 are sure to challenge the 4K max 240Hz position we currently have on gaming monitors.
Most people don’t need that extra refresh rate, but let’s be honest; most people also don’t need to spend $1,600 (or even $1,000) on a GPE.
We have the hardware
Oddly enough, we don’t have to wait for the hardware to take advantage of the monitors. We are waiting for the monitors to show off the new hardware. Samsung already teased its “8K” Odyssey Neo G9 for this year’s CES — for the record, it’s not true 8K, but two 4K displays side-by-side in a 32:9 aspect ratio — and we expect to see at least a handful of 8K gaming monitors that will be displayed at the exhibition next to the Samsung display.
This screen is also a good touchstone. Assuming Samsung wants to keep the 240Hz refresh rate as the current version, you’re looking at a data rate of over 45Gbps with HDR on (36.19Gbps with HDR off), and that’s with 3:1 compression. This is all theoretical at the moment, we’ll have to wait to see this display and other 8K options, but the numbers suggest that the RTX 4090 may not be able to drive them due to its DisplayPort 1.4a connection (at least at full refresh). speeds, DisplayPort is backward compatible).
This conversation doesn’t have to be limited to 8K or super high refresh rates at 4K either. OLED TVs posing as gaming monitors are becoming more and more popular and we could see the big advantages of 5K and 6K resolutions. As I saw with LG’s UltraGear 48 OLED, the pixel density needs to be higher for such a large display so close to your face. DisplayPort 1.4a can drive 5K and 6K with DSC, but not at refresh rates above 120Hz and not at higher HDR color depths.
This data rate limitation also shows up in VR. The Pimax Crystal, which is currently a Kickstarter campaign, should claim around 29 Gbps of data with DSC at 3:1, according to the specs. This is within what DisplayPort 1.4a is capable of, but it’s hitting a limit.
From large format displays to VR headsets to higher refresh rates at 4K, DisplayPort 1.4a is starting to reach its full potential. If AMD and Nvidia stuck with DisplayPort 1.4a, it wouldn’t be a big deal. Display manufacturers would adapt to the capabilities of the current market. But AMD is opening the door with its new GPUs.
An important difference, but not a selling point
Of all the things you can decide to buy, the DisplayPort standard should be very high on that list. We still have to see how AMD’s new GPUs perform, what features like FidelityFX Super Resolution (FSR) 3.0 will bring, and whether overcoming the barriers that gaming monitors have at all makes sense.
But that’s where the trend is going, and the difference between DisplayPort 1.4a and 2.1 could become more important much faster than we expected – at least for the high-end gamers who want to experiment with the latest technology.