One week with the Valve Index: A VR game-changer with a few question marks

My introduction to the Index, Valve's first-ever top-to-bottom PC virtual reality system, was a whirlwind of numbers and demos. Valve's three-hour hands-on event in April came with a considerable blast of specs, claims, and pre-release software, but while those ranged from puzzling to impressive, none of them stayed with me like one off-hand comment from the day.

During an informal Valve Q&A after my tests, I talked about how impressed I'd already been by the Oculus Quest's "good enough" performance as a wireless, standalone VR headset. How would the pricier, wired, more demanding Valve Index fit into that kind of marketplace, I asked?

"I don't use VR for 30 minutes a day," one Valve engineer said in response. "I use VR hours a day. What's good enough for 20 minutes, 30 minutes, is dramatically different than one hour, two hours."

This engineer was on to something that couldn't be sold in a whirlwind press event: the Index difference in the home. I've been testing that angle for nearly a week thanks to an early Index shipment that Valve is letting press discuss in a "preview" capacity—meaning, this is not a fully fledged review ahead of the system's June 28 launch ($999 for the full Index system, $499 for just the headset without its required "lighthouse" tracking boxes or any controllers). A lot could change in a month.

Instead, this piece revolves around that Valve engineer's implied suggestion: strap into a Valve Index for hours at a time, make it part of my workday, and see the resulting difference. These tests (which include typing the majority of this preview with an Index as my "monitor") have been telling. Valve Index isn't perfect by any stretch, but it is absolutely the first VR system I can use for long periods of time without feeling "VR swimminess." Until someone else shows up with a system that exceeds Index's weaknesses and capitalizes on its best improvements, I do not see myself switching back to another PC VR headset.

Playing the field... of view

As a recap: the complete Valve Index package includes a headset, a pair of controllers, and a pair of "lighthouse" tracking boxes. These are all compatible with other existing SteamVR devices—meaning, you can mix and match the headsets, controllers, and tracking boxes from the HTC Vive, HTC Vive Pro, and Valve Index (and thus buy less Index hardware if you want to reuse elements that you already own). In very good news, I was able to plug and unplug elements from all three of those systems on the same PC, boot back into SteamVR's software, and enjoy full compatibility, even in the Index's very early preview period.

[Update: There's one exception to the above mix-and-match scenario. The original HTC Vive's controllers will not work with SteamVR 2.0 tracking boxes. The Vive Pro's wands do support SteamVR 2.0. If you want to combine old Vive wands with newer Valve Index hardware, keep your SteamVR 1.0 tracking boxes handy.]

I'll start with the headset, which I'll call the "Index" from here on out for simplicity's sake. You've seen headsets like this before, with a ski-goggle strap, hovering speakers, and a pair of high-resolution panels translated by a pair of curved Fresnel lenses to simulate a virtual reality sensation. Connect it to a "gaming"-grade PC, strap it over your head, then either stand up in a room with cleared floors or sit in a comfortable chair. Use either a pair of hand-tracked controllers or standard hardware like keyboard, mouse, and gamepad to play with software while you're transported to another world.

The Index difference begins with a noticeably boosted field of view (FOV) compared to the competition. VR users in general can expect to have their peripheral vision blacked out to some extent, thanks to inherent limitations from a pair of lenses. The Index is no exception, but Valve promises "20 degrees more" FOV than any existing consumer-grade VR headset on the market—no matter what size of face or pair of glasses you bring into the headset.

If you strap into an Oculus or HTC headset, you can expect a "maximum" FOV of roughly 110 degrees, but that number shrinks if you have bulky glasses or an awkward face fit into the headset. Index, on the other hand, has placed its pair of LCD screens on a mechanical array that does two clever things: it applies a 5-degree "canting" angle to the screens, and it includes an additional FOV-specific slider to let users bring those lenses as close to their cheeks or glasses as is physically comfortable.

Index's FOV difference is absolutely noticeable for average, no-glasses users. As I noticed at the Index reveal event, the best showcase for this difference comes from widescreen-ratio videos, and I've since watched quite a few of those in my Index. I have gotten into the habit of booting into SteamVR's Virtual Desktop app (which I prefer over SteamVR's built-in desktop-mirror option), loading full 4K-resolution videos, and positioning them to simulate the feeling of sitting in a "perfect" movie theater seat—not too close, not too far. I can do this with the Valve Index and expect to sit roughly two "rows" closer to the video image than I can with the HTC Vive Pro.

Add my large, Seattle-hipster glasses to the mix, and that difference jumps a whole 'nother two rows. Index accommodates glasses in a more comfortable manner than any other consumer-grade VR headset, period.

Index has some sexy pixels

Those metrics, by the way, simply account for how many visible pixels fill out the peripheral view in VR. Where the Valve Index absolutely trounces the likes of the HTC Vive Pro and Oculus Rift S (let alone the original Vive and Rift) is the peripheral pixel quality.

Rift S arrived earlier this month with an admittedly boosted subpixel resolution and widened "sweet spot" compared to the competition. The latter term speaks to the common issue with VR headsets where peripheral pixels look blurrier or less focused than the center ones, which can be blamed on anything from lens construction to display panel orientation.

Where Rift S subtly improved those factors, however, Index steamrolls the competition. This is most evident when using Index while typing and mousing around a Windows desktop while wearing the headset. When I peripherally peek at a chat interface and a Twitch video stream while typing in a central window, the resulting peripheral pixels are still admittedly a tad blurry, but not as much as with last-gen headsets, and peripheral smearing doesn't begin until the roughly 105-degree point on Index. On the Vive Pro, that peripheral smearing starts at roughly the 80-degree point and is more severe.

Valve's sales pitch of long-term VR comfort within Index is 100% legitimate.

There's also the matter of subpixel resolution getting a considerable boost across the entire pair of panels, which probably helps the peripheral view as much as the central stuff. Valve is absolutely right: it has engineered the crap out of the "screen door" effect of visible pixel separation, especially compared to the otherwise stunning Vive Pro. Look at a giant white field of pixels on HTC's OLED headsets (like you'd see in an average desktop webpage), and you'll see tons of black "crackling" between each tiny white pixel. This effect is forgivable enough within brief or high-action VR activities, but it's a pain to deal with at length while VR-desktopping.

Look at the same Windows desktop content on Index, and you'll still notice pixelation, where the VR headset must correct for aliasing. This high-res headset doesn't make the sheer issue of pixelation somehow disappear. But thanks to Index's richly engineered LCD panels, you honestly won't notice a screen door.

Thoughts on frames and on hours of uninterrupted Index time

On top of those boosts, the Valve Index's high-res panels can operate at a 120Hz or even 144Hz refresh rate—much higher than the "90Hz gold standard" on first-gen headsets, let alone the "good enough" rate of 72Hz on the wireless Oculus Quest. Is the difference noticeable?

I briefly toggled the 144Hz option on my beefy, VR-ready PC (I7-8770K CPU overclocked, Nvidia RTX 2080 GPU overclocked, 32GB RAM), but I immediately scaled this down to 120Hz. SteamVR's software includes automatic resolution-scaling options for the sake of running software at a preferred frame rate, and going up to 144Hz on my machine resulted in a noticeable slash in pixel resolution—still dense enough but officially bad enough to expose jagged pixelation in my FOV. This happened while testing "simple-geometry" fare like Beat Saber and Job Simulator in 144Hz mode, and their noticeable jaggies definitely weren't worth the extra frames.

In better news, my system could get to a comfortable, high-res 120Hz refresh on nearly every game and app I tested. (We'll dig into a range of PCs and software for our eventual review.) All in all, I wasn't exactly enchanted by the results. I love my 144Hz gaming monitor, but once a game gets above 90-95Hz, I honestly can't perceive a difference...

...until I get into a traditionally tricky genre for VR gaming: high-speed racing. Holy cow, folks. I have gone on the record as being Ars' most sensitive VR gamer, the kind who becomes mayor of Puketon, Massablewsetts when a VR game pushes uncomfortable tricks like lateral movement. But booting into the sim-racing game Project Cars 2 on the Valve Index was a revelation, and I'm prepared to start charging people $20 to play 15-minute PC2 sessions on my home's Index rig. The full Index experience—higher frame rates, clearer peripheral pixels, and a wider FOV—unlocks something phenomenal in the brain that makes high-speed racing a far more approachable and comfortable VR prospect than ever before. (While I enjoyed similar thrills in the future-racing VR game Redout, that game had some serious washed-out color issues within Index, perhaps owing to Index's pre-release state.)

Other "room-scale" VR fare like Beat Saber and Space Pirate Trainer already benefits from clear frame rates and responsive tracking on the best rival headsets, and I could barely perceive an Index difference based on frame rate alone. More frames are better, sure, but I need more time to pick through my VR game and app catalog to issue a verdict on this front. Additionally, a quicker display refresh rate may contribute to my increased comfort while using Valve Index for hours at a time, but I want more testing time to figure that out, as well.

Still, I'm not sure that I have a font big enough or italics angled enough for this sentence: Valve's sales pitch of long-term VR comfort within Index is 100% legitimate. Every aforementioned design tweak and system element comes together to make the Index a system I can seriously use for long periods without feeling major vision fatigue or post-VR dizziness. I need more time with the Index to answer how its weight balance truly plays out for long-term use cases (more on its head strap in a moment). But in terms of having a weighty headset stuck to my face and pumping light into my eyeballs for hours at a time, Index is currently the best product for that use case on the market, and not just by a nose.

Unlike a Tinder date, Index won't ghost you

The worst news about the Valve Index's panels is their reliance on LCD technology as opposed to OLED. Index's fast-switching pixels are absolutely on par with OLED in terms of minimal "ghosting" effects (though I struggled to confirm whether Index is actually better than the Vive Pro in that regard), but color reproduction and black levels are not pristine. I said the same about the Oculus Rift S and HP Reverb, and while Index is a noticeable smidge above the Rift S in terms of color reproduction, there's still a slight emphasis on blue-green tones that makes giant, open skies and colorful world details look the slightest bit washed out compared to the Vive Pro.

Also, if you've gotten used to the very, very deep black levels on OLED VR headsets, get ready to bid those adieu. Light bleed is the ultimate LCD-panel drawback, and Index does not include any sort of "QLED" tweak to work around the light-bleed realities of LCD technology. If you're not a fan of light bleed in the new Oculus Rift S, be warned: the Index is in a similar ballpark (but, again, its screen-and-lens combo has so many other positive qualities that it's arguably much easier to tolerate).

And if you saw my comments above about the Index as a great widescreen-video device, you'll have to hold out hope that Valve updates the device's color management to alleviate some serious black crush issues that I noticed in my preview hardware. The first 15 minutes of the original Matrix film are an incredible stress test for color and contrast reproduction, thanks to its boldly framed scenes of contrasting darkness and light, but watching these on Index revealed an utter obliteration of darker video content, including the details on a trio of agents standing in front of a bright spotlight.

This is made doubly tragic by some very good news for Index users: a noticeable and welcome drop in "god rays" compared to other retail VR headsets. Watching the same Matrix scenes on my Vive Pro came with more accurate color reproduction, but that enjoyment was interrupted by distracting, circular light bounces all over my FOV. The Index still has some noticeable god rays, but they're a bare minimum, not much worse than the bright-light effects you might notice while wearing thick glasses at a real-life movie theater. I say "doubly tragic" about this because I would love for those reduced god rays to have been met with better handling of dark and black tones.

In a back-and-forth email chain with Valve representatives about various Index testing concerns, my questions about the Index's black crush issues, and whether they may be remedied ahead of the headset's launch, were not acknowledged as of press time.

Straps, microfibers, and speakers

The Index headset's fit doesn't otherwise reinvent the wired-VR wheel. VR fans have definitely seen this kind of "ski-goggle" fit before, and at a full Index headset weight of 809g/1.786lb, the strap can only go so far to balance that weight across a user's head. (To compare, the Vive Pro weighs in at 832g; PlayStation VR's headset weighs 647g; and the Oculus Rift S weighs 600g.) But the mechanism to extend the back of the headstrap goes a phenomenally long distance, and between that and a pretty spacious interpupillary distance (IPD) slider, I would anecdotally declare this the most comfortable VR headset for giant noggins I've yet seen. (If you have a particularly tiny head, meanwhile, the Index includes a squishy tiny-head insert that you can attach to the headstrap.)

The default microfiber-cloth material used on this headset's face cushion is a definite upgrade over the standard foam found on the Oculus Rift S and HTC Vive Pro. It's not quite up to par with pricier third-party leather face cushions, but I'm glad to see Valve pick this breathable material as a shipping default. We're still in clamped-on-face territory, however, so if you bring a lot of heat into the Index headset, you'll still steam up and sweat as much as any other wired-VR option out there. (Meaning, Valve hasn't implemented any sort of revolutionary ventilation or fan system.)

Meanwhile, the Index's pair of floating, directional speakers are certainly welcome, in terms of pumping high-quality audio without touching your ears. These speakers do a remarkable job of delivering believable 3D-positional audio while juggling an impressive range of sound frequencies. (I'll have more on positional audio in our eventual review.) The biggest complaint I currently have about the speakers is their somewhat paltry maximum volume. A lot of content I've played on Index, set to 100% volume, has sounded kind of loud but far from booming. This is compounded by the speakers' distance from ears, which means any background music I might have playing in my home, even at freakishly low volumes, surprisingly crowds out the Index's speakers.

Thus, if you want to guarantee a sense of Index audio loudness, you'll need to silence any background noise or music in your playspace of choice. As someone who loves having a constant stream of background music in my home (shoutout to Seattle's KEXP), this is no small concession on my part, but I may be an edge case there. And even with my home speakers silenced, I'm surprised that I can't crank these speakers even a little bit louder.

Boxes, frunks, and watch lists

The full Valve Index "system" is rounded out by a pair of Valve Index Controllers and a pair of lighthouse tracking boxes. You cannot use the Index without at least one tracking box, but you'll need at least two to make sure the headset and controllers can be tracked from all angles without occlusion. (These tracking boxes rely on the same infrared technology as the original HTC Vive, which you can read more about here.)

My review unit came with a pair of "SteamVR 2.0" tracking boxes, which employ a slightly wider cone of lasers, support for larger rooms, and compatibility with up to four boxes in the same space. If you already own first-gen SteamVR tracking boxes, like the ones that came with the HTC Vive, you can leave those plugged in and expect perfect compatibility with the Index. After confirming that in some testing, I went ahead and set the 2.0 boxes up in my playspace. This confirmed a nice surprise: both tracking box types use the exact same power plug. I was able to unscrew my 1.0 boxes on my existing ceiling mounts without having to rewire their required power cords. Thank you for that, Valve.

But yes, that's a good reminder that you're still in wired-sensor territory with Valve Index. Worse, users are encouraged to set them up at a high, downward-facing angle, and while they'll still work if you can't nail them to a ceiling or don't have a nearby shelf, you lose some tracking accuracy if you can't guarantee their top-down view.

Having been quite impressed by weeks of using the Oculus Rift S' inside-out tracking system (and the slightly less-capable sensing of the Oculus Quest), I'm still bummed that Valve has held so stubbornly to this tracking-box requirement. I could understand Valve's stance compared to the truly incomplete tracking of two-camera Windows Mixed Reality headsets, but Oculus' elaborate "Insight" camera system has changed the VR game. Valve needs to step this part of the Index ecosystem up, and soon.

Maybe the Index's "frunk" compartment, which hides a USB 3.0 slot in the headset's front, will enable some built-in multi-camera attachments in the future. But no such devices or related Index announcements yet exist. In fact, our review hardware came with zero documentation about the frunk slot. I plugged a USB memory stick into that bad boy to confirm that it works like a standard USB slot, but that's all I got. Consider this an open call, dear readers, if you want to send any suggestions for what to test. (I'm hesitant to request that readers send me their personally MacGyvered gizmos, if only because I don't want to wind up on a federal watch list after a bunch of frunk-minded circuit boards show up at my doorstep from random worldwide addresses.)

Knuckling down with Index's controllers

The last parts of the Index ecosystem are officially known as the Valve Index Controllers. But I prefer their original codename of the "Knuckles"—it's shorter, it's descriptive—so I'm sticking with it.

That name comes from how these controllers clasp around the knuckles on your non-thumb fingers so you can let go of the plastic handle at any time and guarantee two things. First, you can let go and easily wiggle your fingers around, which are then translated by an array of 87 sensors. If a game or app has been updated with Knuckles support, your fingers should then "accurately" appear in your virtual world. Give a thumbs up, some devil horns, or a Dr. Evil pinky, and your VR hand should respond in kind. Second, you can comfortably assume that when you bring your fingers back to the controller's handle, button, and joysticks, your fingers will always find the right bits immediately.

One great thing about the Knuckles is that they admit some defeat in the VR control world and bring Valve's hardware up to control parity with Oculus. Each hand gets a pair of action buttons, a clickable joystick, a trigger button, and a grip button. That's the same as Oculus Touch. Good. Your favorite VR game may very well ignore that button array and keep things VR-simple, with hands and triggers doing the bulk of the work, and that's fine; even in that case, you're still getting the very comfortable boost of the Knuckles' microfiber, elastic binding material. The awesomeness of fully releasing handheld controllers in the middle of a high-intensity Beat Saber song cannot be oversold. Only the Valve Knuckles can afford this.

Simply put, if your favorite VR game relies on nothing more than pointing, aiming, and pulling a single trigger button, the Knuckles are the best and most comfortable option in the VR marketplace. Which, gosh, is the least you can expect from a $279 pair of VR controllers.

However, everything else about Knuckles feels a little too early to definitively review or criticize. First off, I had finger-sensing issues at the Index's reveal event, which Valve engineers kept insisting was because the controllers had to continually re-calibrate when new users stepped in. But I was a few hours into one day's testing at my home when I booted the same hand-tracking demo from that event, developed by Cloudhead Software and featuring Portal-styled Personality Cores, and I once again had the same issues.

Issues with legacy software, dainty gestures

If you're wondering: typing with the Valve Knuckles strapped to your hands is possible but hardly ideal, mostly because the hardware gets in the way of free thumb movement.

Credit: Sam Machkovech

Holding up a single pinkie finger, extending a middle finger, spreading all my fingers out, and having my fingers semi-clasp around the grip: roughly 5% of the time, each of these gestures resulted in glitchy, inaccurate VR finger replication. Like, I might need to redo the gesture once to see it accurately appear in VR, or wiggle my fingers to convince Index that, no, my ring finger is not raised.

Will I need to guarantee perfect pinkie placement in some eventual, killer Knuckles game or app? Probably not. But Valve is charging $279 for a pair of these controllers with a sales pitch of pristine finger tracking, and without any showcase software, I'm left with plenty of time to look at my hands and nitpick the VR results.

The two other unique Knuckles features are a force-sensitive "pinch" button and a palm-sized, force-sensitive grip panel. I honestly like the grip panel as a facsimile for grabbing onto VR surfaces with my real-life hands, which I was able to test in a Knuckles-enabled version of the indie VR game Climbey. It's nice to have that abstraction feel slightly more real, and thus make a wall-climbing simulator feel all the more exciting when I pull off crazy maneuvers. Also, I was able to hold up fingers (or, uh, just one finger) and take silly selfies in a test version of the solid game Vacation Simulator. But the latter game did not implement interesting Knuckles use in any other way, and there really just isn't much Knuckles-specific content available for testing yet. That will surely change as we get closer to Index's retail release date.

Meanwhile, the pinch button, which is concave and designed for your thumb to rest on, replaces the HTC Vive wands' massive, circular trackpads, and it's shrunken to the size and shape of a thumb. If your favorite old SteamVR app relied heavily on that trackpad, this thumb-sized button does not adequately emulate its touch sensitivity, especially for lateral, side-to-side thumb gestures. Valve explained to Ars that it made this shift because the engineers noticed that a majority of VR apps never used that side-to-side functionality. But in my testing period, I kept running into "unpopular" older games that relied pretty heavily on that kind of trackpad use. That's the thing about VR: for every Beat Saber, there are dozens of games that are beloved by subsets of VR's small audience.

With that in mind, we're waiting for Valve to implement Knuckles-minded control corrections for, er, every SteamVR game that relied on the Vive wands. And a lot of games desperately need them. One of my all-time favorite SteamVR games, SuperHyperCube, relies on the Vive's trackpads for its block-rotation system. I went through a slightly complicated menu-hop to build my own custom Knuckles controls for that game, which I appreciated being able to do. I thought translating all of its functions to the Knuckles' joysticks would work just fine. But SteamVR doesn't let users adjust the joysticks' dead zones, and in games like SuperHyperCube, that means a trackpad-to-joystick transition is impossible to replicate in comfortable fashion. I'd tap "left" once and watch as the game twisted my floating cube left, up, down, and left in one disorienting swoop. Ugh.

Some games already have Knuckles-specific controller modifications built and implemented by Valve, but as of press time, many don't (including critical VR darlings like Thumper). One that did, the frantic Doom VFR, suffers from a similarly weird translation from trackpads to joysticks—and needs a serious dead-zone adjustment option, as the game's constant dodge-step function is currently hard to accurately orient on Knuckles. Another one, Fallout 4 VR, did a much better job mapping its trackpad functions to joysticks. (Both of those Bethesda-published games, I should point out, scale up very well to Index's 120fps refresh. I can't go back to the Vive Pro on either of those as a result, since higher frame rates definitely increase the comfort for "virtual walking" games like those.)

Meanwhile, the Valve-developed binding for the storybook-platformer Moss was broken because I'd adjusted an in-game HTC Vive control option that Valve's automatic system didn't account for. Until I had a back-and-forth email exchange with Valve staffers, I had no idea why my character couldn't swing her sword (a pretty imperative function in the game).

Thankfully, as soon as I figured this Moss settings issue out, I was back in business. Moss controlled wonderfully with the Knuckles' array of joysticks and buttons, and the combined build quality and resistance of each was quite good. I felt quite comfortable moving my thumbs between Knuckles' joystick and button halves, as well, but it's definitely trickier to establish an exact "directly up," "directly right," orientation for its joysticks than with the Oculus Touch controllers, which fit into the hands with a much more neutral joystick-to-thumb angle.

Again, this is not a review

At this preview stage, I have a bad feeling about the chicken-or-egg problem of Knuckles adoption to drive more interesting SteamVR software, such as the hand-tracked craziness of Boneworks (an upcoming game that we've yet to play outside of press demos). Without a stunning, Super Mario 64-caliber example of Knuckles' potential in my hands, I'm currently left with slightly wonky finger tracking and a question mark of whether I'm going to face software headaches going forward.

Meanwhile, the cheap, serviceable Oculus Touch controllers are not compatible with SteamVR's lighthouse tracking boxes (they require an Oculus headset), and there's no cheap Touch-like controller on the SteamVR horizon to otherwise help gamers join the better-control party. Maybe we'll get a cheaper Knuckles Lite down the road? Or, perhaps there's some better solution for VR control standardization across SteamVR, Oculus, and Windows Mixed Reality so that I don't have to rely on a SteamVR hack on top of my favorite software?

Had Valve sold the Knuckles at a price comparable to average game controllers, by the way, I'd sing a much different tune. The general immersion afforded by their comfortable fit and button arrangement is fantastic, and if money's no object, they're the best VR controllers on the market. They certainly beat the pants off the HTC Vive's wands (which still cost $260 per pair for some reason).