What you need to know about HDR for PC gaming

If you’ve been waiting for HDR to arrive on the PC, there’s news both good and bad. The good news is that the PC pathway to hardware HDR was finally set at CES earlier this year, with the announcement of several gaming-grade desktop monitors supporting HDR10. Heavy hitters in PC displays like ASUS, LG, Acer, Samsung, and Dell have all announced HDR gaming monitors, and the specs are generally impressive.

The bad news is right now this doesn’t matter much. HDR’s chaotic tangle of standards has gotten worse over the last year, and despite the flood of announcements, only a handful of HDR-equipped desktop displays have made it to the marketplace as of summer 2017. Some, such as Dell’s U2518D, don’t fully support all of HDR10’s requirements while others, like ASUS’s perfect-on-paper ROG Swift PG35VQ remain harder to find than Sasquatch.

Samsung’s new lineup of Freesync2 HDR monitors is capped by the 49” C49HG90, which runs an unusual 3840x1080 resolution, or exactly twice as wide as 1080p.

On the software side, the PC’s second-class status when it comes to HDR game releases continues to sting. Console gamers get first consideration while games for Windows trickle out with all sorts of strings attached. Moreover, changes made to HDR in Windows 10 via the Creator’s Update caused problems with HDR on systems using Nvidia graphics cards, which only the latest drivers seem to be clearing up. It’s a mess.

Frustrated? Don’t feel bad; when it comes to issues with HDR, that’s just the tip of the iceberg. So just what is HDR and what can it do for gaming? This first question is easy to answer. The second, however, is going to take a little time…

Many games have supported "HDR lighting" for years, but that's not the same as real HDR display technology.

What is HDR

HDR, or High Dynamic Range, is an umbrella term for a series of standards designed to expand the color and contrast range of video displays far beyond what current hardware can produce. Despite what you may have heard during the headlong push to 4K, resolution is pretty far down the list when it comes to image quality. Beyond roughly 110 DPI under current Windows UI scaling limitations, the number of pixels starts to matter much less than what you do with them.

Hardware HDR goes far beyond the simulated HDR found in older games like Half-Life 2.

Contrast, brightness, and vibrant color all become more important to image quality once resolution needs are met, and improving these is what HDR is all about. It’s not an incremental upgrade either; HDR’s radical requirements will mean new hardware for almost everyone and a difference you don’t need a benchmark or trained eyes to perceive.

For starters, HDR specs require a minimum 1000 cd/m2 or nits of brightness for LCD screens. High-end desktop gaming monitors, which top out around 300-400 nits in brightness, don’t come close to making the cut. Good laptops don’t fare much better, since they only push about 100 nits or so more. Even cellphones, with their sci-fi sunlight-viewable screen technology, only reach about 800 nits. When it comes to brightness, HDR-compliant screens leave all these displays in the dark. 

Luminance explained.

Color also gets a makeover with HDR specs requiring a full 10- or 12-bit color space per channel, which is fully accessible across the OS and managed via a set of active standards. Most PC displays only provide 6- or 8-bit color per channel using a subset of the full color space called sRGB, which covers a tiny third of HDR’s visual spectrum. However, even when the hardware is available to do more, software peculiarities make using legacy enhanced color modes cumbersome.

sRGB, on the right, provides just a third of colors available to HDR.

Currently, PC monitors that support wide gamut color, or WGC, generally reserve compatibility for professional use, such as image processing or medical research applications. Games and other software simply ignore the extra colors and often wind up looking misadjusted when the reduced color space they use is mapped onto wide-gamut displays, unless the hardware takes special steps to emulate the reduced color space. 

HDR standards avoid the confusion by including metadata with the video stream that helps manage the color space properly, making sure applications look correct and take optimal advantage of the improved display capabilities. To help handle all the extra data, some HDR variants usher in HDMI 2.0a as a minimum display connector requirement; a long overdue upgrade on the ubiquitous low-bandwidth HDMI 1.4 standard.

Wide-gamut color is only part of the HDR equation. Eizo’ ColorEdge professional series, for example, support WGC but aren’t even close to HDR compatibility, despite their quality, cost and excellent reputation.

Standards are great. Everybody should have one.

HDR has plenty of promise, but the road ahead isn’t clear yet. The biggest problems aren’t technical roadblocks but competing, partially incompatible standards that threaten to detour early adopters into expensive dead ends. 

No less than five HDR standards currently exist, although most of the time it comes down to two: the proprietary Dolby Vision which features 12-bit color and dynamic metadata vs. the open standard HDR10, which supports 10-bit color and only provides static metadata at the start of a video stream. 

Dolby Vision, with its license fees and extra hardware, is the more expensive implementation which has slowed its adoption. Most gaming hardware manufacturers and software studios have opted to support HDR10 instead, significantly including Microsoft for the Xbox One S and Sony for the PS4 and PS4 Pro. This indicates the way the gaming industry is leaning, but recent developments have shown the format war is far from over.

Proponents of Dolby Vision tout its greater color depth, more demanding hardware standards, and frame-by-frame ability to adjust content on a dynamic basis, along with its HDR10 compatibility, but gaming is moving towards the cheaper, good-enough standard of HDR10 by itself.

HDR10 proponents Samsung and Amazon have pushed back against image quality arguments with an upgrade to the format called HDR10+, designed to address some of the earlier implementation’s shortcomings. 

Since HDR10 uses static data, very bright or dark content means trouble rendering the occasional scenes shot at the other end of the spectrum, which can appear either murky or blasted out. HDR10+ adds Dolby Vision-style dynamic metadata and eliminates this problem. HDR10+ also keeps the open source model that made HDR10 so easy to for manufacturers to adopt.

HDR10 isn’t compatible with Dolby Vision, leaving Dolby’s superior but proprietary and more expensive HDR standard out in the cold when it comes to gaming. However, if you’re a video or film enthusiast buying based on image quality and content already graded and available for Dolby’s superior standard today, this may not matter so much and you’ll enjoy a better picture immediately. Netflix for example is particularly interested in Dolby Vision, with almost all their internally produced content supporting it. Vudu and Amazon also offer Dolby Vision content.

The latest twist? A recent update to Dolby Vision has moved the standard entirely to software, making it possible for games and video cards to support the standard more easily via patches, firmware, and driver updates. With Nvidia baking in support since March and titles like Mass Effect Andromeda already patched to include Dolby Vision, the format war isn’t over when it comes to gaming either.

In case you’re wondering, the other two HDR standards are HLG, or Hybrid Log Gamma, developed by the BBC and used on YouTube; and Advanced HDR by Technicolor, used largely in Europe, which allows playback of HDR content on SDR display via tricks with gamma curves. 

Where can you find HDR today?

PC display manufacturers may be dragging their feet with promised products, but you don’t have to wait for them to try it out. Hardware HDR has already arrived for consumers in the high-end television market. This is also the best way to see the difference HDR makes in action, as a growing library of HDR demos, films, and television shows make side-by-side comparison simple. It’s also a lot easier to justify the sizable expense of an HDR upgrade when the display serves double duty as an entertainment room showpiece. 

Thanks to console gaming’s embrace of HDR and the living room as a gaming space, some of these sets, such as LG’s C6 & C7 series, can pull double duty as impressive computer displays that allow exploration of first-wave HDR content as it becomes available on the PC. 

For example, the C7 I've tested uses an OLED panel thinner than an iPhone, supports all current HDR formats, 4K resolutions at 60Hz, 120Hz refresh rates at 1080, and Dolby Atmos sound: a wish list of features desktop displays can’t touch right now. The latest firmware updates for the series bring gaming mode input lag down to 21 MS, not far behind some 34-inch desktop displays and fine for most gaming needs. 

With virtually identical 55-inch C6 and B6 models from 2016 available for under $2000, this remains the HDR panel to beat for PC enthusiasts looking to dabble with the format while the desktop display marketplace and PC gaming’s HDR release schedule sort themselves out. 

With the same investment, you’ll be able to watch any kind of HDR content, hook up any console, and enjoy HDR PC titles as they become available. Just keep in mind that using a TV for PC gaming has a few idiosyncrasies you should read up on before pulling the trigger.

HDR PC monitors

Here are all the announced HDR PC monitors so far, their specs, and what we know about price and release information. Keep in mind that even the monitors available now may be sold out at retailers. Excluded from this list are the Dell S2718D and LG 32UD99, "HDR" monitors that can accept an HDR10 signal, but lacks the color range or luminace to properly output by HDR10's standards.

Samsung CHG90
Size: 49-inch curved
Resolution: 3840x1080
Panel: VA
Refresh: 144 Hz
Adaptive sync: FreeSync 2
HDR: FreeSync 2
Price: $1500
Release: Available now

Samsung CHG70
Size: 27-inch or 31.5-inch curved
Resolution: 2560x1440
Panel: VA
Refresh: 144 Hz
Adaptive sync: FreeSync 2
HDR: FreeSync 2
Price: $599 and $699
Release: Available now

BenQ SW320 *
Size: 31.5-inch
Resolution: 3840x2160
Panel: IPS
Refresh: 60 Hz
Adaptive sync: N/A
HDR: HDR10
Price: $1490
Release: Available now
* While the SW320 has the proper color depth and color space for HDR, it does not meet the brightness requirement for true HDR10 support.

Acer Predator X27
Size:
27-inch
Resolution: 3840x2160
Panel: IPS
Refresh: 144 Hz
Adaptive sync: G-Sync
HDR: G-Sync HDR, HDR10
Price: Unknown
Release: Q3/Q4 2017 

Asus ROG Swift PG27UQ
Size:
27-inch
Resolution: 3840x2160
Panel: IPS
Refresh: 144 Hz
Adaptive sync: G-Sync
HDR: G-Sync HDR, HDR10
Price: Unknown
Release: Q3/Q4 2017 

Acer Predator X35
Size: 35-inch curved
Resolution: 3440x1440
Panel: VA
Refresh: 200 Hz
Adaptive sync: G-Sync
HDR: G-Sync HDR, HDR10
Price: Unknown
Release: Q4 2017

Asus ROG Swift PG35VQ
Size:
35-inch curved
Resolution: 3440x1440
Panel: VA
Refresh: 200 Hz
Adaptive sync: G-Sync
HDR: G-Sync HDR, HDR10
Price: Unknown
Release: Q4 2017 

Graphics cards

One place where PCs are already prepared for HDR is the graphics card market. While monitors lag behind their TV counterparts in HDR implementation, mid- and high-end GPUs have been ready for the revolution for almost a year now, thanks to the healthy rivalry between Nvidia and AMD.

Nvidia has been talking up HDR since its last gen cards, and currently certify all Pascal-based cards as HDR ready as well. AMD is slightly later to the game, with the 390X and Polaris lineup their first HDR-capable cards, so if you bought a graphics card recently there’s an excellent chance that at least part of your system is good to go, at least at 1080p. If you’re looking to use that new HDR display to the fullest, you’ll need to step up to the latest top shelf graphics cards since 4K-class native resolutions are almost always along for the ride.

Lest you think this was one area of HDR not beset by completing formats, Teams Red and Green are doing their best to replay the adaptive sync wars. Each has introduced individual implementations of HDR tied to G-Sync and Freesync technology, called G-Sync HDR and Freesync 2 respectively, and how nice they will play with each other remains an open question.

What about games?

The trickier question is what all of this means for PC gamers. While some new games will come out of the box with HDR in mind, older software won’t support the wider color and contrast capabilities without patching. Those older games may play normally on HDR-equipped systems, but you won’t see any benefits without some fresh code added to the mix.

Fortunately, leveraging HDR’s superior technology doesn’t require a ground-floor software rewrite. A fairly straightforward mapping process that expands SDR color maps to HDR ranges via algorithmic translation can be used to convert SDR titles without massive effort.

Hitman is one of the few games to support HDR on PC, Xbox, and PS4.

The real problem facing PC gamers interested in HDR today is that it has barely arrived. Just a handful of games support hardware HDR right now with Shadow Warrior 2, Deus Ex: Mankind Divided, and Hitman (2016) leading the list. Popular cross-platform titles such as Gears of War, Battlefield, and Forza Horizon 3 feature HDR in their console versions but not on the PC. Nvidia was actively working on a Rise of Tomb Raider patch, but a proper PC version never materialized. Here's the full list of HDR-enabled games on PC so far:

  • Shadow Warrior 2
  • Deus Ex: Mankind Divided
  • Hitman (2016)
  • Resident Evil 7
  • Mass Effect: Andromeda
  • Obduction
  • Paragon
  • Need For Speed: Payback (upcoming)
  • Star Wars: Battlefront 2 (upcoming)

Rise of the Tome Raider’s PC HDR version remains lost in limbo.

Software studios are coming around, but it’s going to be mostly Blu-ray and streaming content for a while, along with the indignity of seeing consoles get access to many HDR enhanced games first. So kick up your heels and chill. It’ll be a while before HDR is properly represented on the PC. For now, just catch up on your Steam back catalog, and use that shiny new HDR television for Netflix until HDR comes to you.