Reverb G2 vs Index and the frustrating state of VR simming

User Support Hub Virtual Reality (VR)
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TLDR G2 should be a clearly better headset (no pun intended) for simming than the Index, but a number of completely avoidable software issues, notably motion smoothing, cast a shadow on its high-res panel and other good features.

Almost 2 months ago, I sent my Reverb G2 in for service and sprung for an Index to use in the interim. Today I finally got my G2 back and have some thoughts on the 2 headsets and a bit of a rant on the current state of VR simming.

The problem that made me send in my G2 was constant problems with the headset tracking. The view would constantly bob and jitter. The deviations were small, but overall it was enough to make VR unusable for more than a few minutes. Sending it in for service seemed like a long shot, but I was out of ideas.

Between then and today, almost 2 months later, a lot has happened. I got a new cable from HP, there have been windows updates, WMR updates, OXR updates, Nvidia driver updates, mobo bios updates. All of this makes it difficult to pinpoint exactly what improved and when. All good though, nothing wrong with a fresh start. I was pleasantly surprised to discover that the replacement G2 does not have the HMD tracking issues as my original unit. I feel like this points to hardware, but it’s kind of impossible to say for certain at this point.

PC specs: 5950x, 3090 FE, 64gb ddr4@3200

The biggest thing I noticed moving to the Index was that the Index configuration seemed to be somehow more efficient. Higher framerate, higher settings, higher resolution. This seemed odd, but since my G2 was gone for service, I could only really speculate.

The first thing I did today was try to get to the bottom of this. I quickly discovered that without any kind of motion smoothing enabled, both configurations were driving about 290 million px/sec (resolution * framerate) with the same settings. Once I enabled motion smoothing, it became fairly apparent what was going on.

Steam’s motion smoothing appears to be far more resilient and robust than WMR’s implementation. I can only speculate at the nitty-gritty details, but I noticed on several occasions that my GPU could be at 98-99%, and the Index’s motion smoothing would be chugging along happily. In the G2, there is an invisible performance threshold, and if you cross it, motion smoothing stops completely resulting in very jarring stutters in the headset. You can break Steam’s motion smoothing, but it’s threshold is much higher than the G2’s. The end result here is that in the G2, you must lower settings significantly to stay far away from this threshold for reliable motion smoothing.

Now I’m faced with the big question.

I have both a G2 and an Index. Which do I want to use as my daily driver?

Honestly, right now I don’t know. For simmers who are cost-conscious buying a VR headset today, I’d say get the G2. It costs less than the Index and has the best panel on the market. If you want to build the best VR sim rig and are willing to spend to get it, you have to make a choice. You have to choose between

  • G2: best resolution, does everything else worse
  • Index: lower resolution, does everything else better

The frustrating part is that this is such an unnecessary dilemma. The problems I’ve outlined above are almost entirely software. None of this would be an issue if:

  • WMR’s motion smoothing was more competitive with Steam’s motion smoothing
  • The G2 ran SteamVR natively instead of WMR
  • Not software, but Valve could just refresh the Index with a higher-res panel

There’s plenty more to talk about in comparing the Index experience vs G2 experience, but this post is already wall-of-text enough. I will just mention that there is currently an issue being widely reported on reddit and other places that a recent software change seems to have reduced the G2’s brightness and/or contrast significantly, and I can confirm. Wearing the G2 is like looking at the Index through heavily tinted sunglasses.

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Sent my G2 in as well, same issue. First they sent a cable assembly, nada. Upgraded the firmware, nada. Then they said send it in which I did and after 4 days I called for an update and they said it needed a part. So I waited, after 2 weeks they couldn’t give me a status. So I complained and a I received a call from customer support saying it needed a part but there was no ETA on it. Next day he said they were shipping the old one back and he’d send me a return label that day and once it was checked in, they’d overnight a new one to me. Problem solved…

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Exact same HMD tracking issue? Interesting. It really was driving me mad. I was experimenting with all kinds of lighting and room conditions. I even tried putting sheets over reflective surfaces and using special studio, non-strobing lamps. At the end of the day it was just… something… in the hardware I guess?

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I have had the Reverb G1 a good while and VR is fantastic.
It took me sometime to find all the windows/Nvidia/Sim settings but once I did there’s no going back to pancake mode.

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I use the Quest 2 with good results but the main issue is that it’s a lot harder than it should be to get it all working. What we need is a proper VR menu system and setup for each headset inside the game, removing the need for all third party tools. Should not be as hard as it is to get it all working.

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I’m a first day VR enthusiast. Started with a DK1 in 2013. I’ve tried almost every visor out there. and my last one was an index. Then… Then i tried G2 and i fell in love. Ok, it hasn’t some pro from Index but it runs smooth with my config (I7 8700k, 2080 Super and 16 Gb ram DDR4) and with the gasket mod i hope to reach the index fov. So for me the choice is G2. And i’m telling this as an old Index owner.

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Thank you for sharing your experience with both! I’ve been struggling between the two for nearly the same reasons and I’ve been exclusively using the Index only for the last 2 months. Your post is motivating me to try the G2 again, with all the latest WMR/OXR/Win10 updates, and see whether it is better now.

I can only speculate about this because we don’t know how WMR motion smoothing is coded. SteamVR motion smoothing is using NVidia VRWorks library (Oculus uses it as well) and this library is computing motion smoothing using the NVidia Tensor Cores. These are the same used for DLSS for example. In using this extra silicon which otherwise does nothing in FS2020, you’re effectively using extra silicon which is not used for the rendering. Therefore the threshold is mostly TDP and bus contention. Whereas WMR might be using the Compute Units (CU) transistors, which are the same as the ones used for rendering. Therefore motion smoothing requires some room and resources from the rendering resources and when you reach a certain threshold in the rendering part, you don’t have any left for motion smoothing.

This is why regardless of Q&A saying FS2020 doesn’t need DLSS because the CAS Shader (or the AMD FFX Super Res. which is supposed to be implemented in the future) is doing a comparable job, I keep advocating for DLSS still because it uses extra silicon power to render a frame, whereas the AMD method is using the rendering silicon which could have been used for the rendering itself otherwise.

[update] more information about DLSS and FSR:
https://forums.flightsimulator.com/t/have-you-looked-into-implementing-dlss-or-fsr-support/385543/4?u=cptlucky8

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I’ve never used an Index, but did have some initial problems with the G2 - completely dead headset after a very brief use. It took months to get a replacement (initially thought issue was the cable) but now that I have received the new unit, I have no complaints. It tracks well and is absolutely awesome to fly with. I am glad I stuck it out and did not give up on the G2.

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I’ve found that clearing environment data in the wmr settings periodically helps stop these small jitters and head movements.

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This makes a lot of sense. I have been so mystified how SteamVR is able to perform motion smoothing with little to no real “cost”. That it would be utilizing tensor cores explains a lot. Really makes me want a different implementation for WMR!

There’s supposed to be a new Vive Pro announced here in a couple of days. Fingers crossed? My Index drives 3K * 3K without breaking a sweat. In fact, it really doesn’t need that much tweaking. The Reverb has to be so heavily tweaked and rendered at a lower resolution. It’s still a sharper picture thanks to the higher res screen. I just want to have my cake and eat it too, that’s all :slight_smile:

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I can’t comment for the Index but I can say I haven’t had any issues with motion smoothing of late. It’s got better and better in recent weeks and the latest patches which allows 90fps driving just 22.5 fps is great. I would say you are correct about driving motion smoothing in the G2, it definately takes a small hit in performance which is the cost of having smoother frames I guess.

A few poeple have said motion smoothing is much better for the G2 using OpenXR and not Steam so having the latest version of this installed and the registry pointing to OpenXR should give you better performance. VR Flight Sim Guy has said it’s now comparable with Oculus reprojection (I.e. for the Quest 2) in MSFS.

Tracking is very smooth and accurate on the G2, always has been, hard to imagine it being any better but lighting conditions can get in the way if poorly setup - I don’t use the controllers. Interesting about the brightness, can’t say I’ve noticed but there was talk of moving this to a configurable slider and I’m wondering if we’re seeing a slightly less bright display might be a consiquance of that, which is ok if they give us the UI to change the brightness but again I’ve not noticed.

My experience in the G2 is phenomenal and no where near what I would describe as frustrating. I have an i9 9900K @ 4.7Ghz, 64 GB RAM and 2080 Ti so not a top end system but decent and more than enough to give a fantastic VR experience.

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I think you may have misunderstood the theme of the original post. The frustration I referred to in the original post came from doing detailed side-by-side comparisons of the Index and the G2. Anyone who doesn’t have both headsets would be none the wiser.

The real takeaway here is that the Index configuration can drive significantly more pixels than the G2 configuration can. With the Index, I can run 3K * 3K pixels at TAA 100 + OXR 100 with most settings on ultra. The Index just doesn’t have the panel to display this image like the G2 does. The only thing stopping the G2 from being able to do this is, as far as I can tell, a software implementation that is less robust than Valve’s implementation.

THIS is the frustrating part. It’s not that we don’t have the tech, it’s just that the G2 has to make do with dollar store drivers and runtimes while our Valve brothers are tapping into powerful graphics APIs with access to of up to 6-to-1 motion smoothing that seems to cost almost nothing performance-wise on any VR app they fire up.

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Ah I’m sorry @cymantix I did read your post incorrectly. And yes I agree there is a performance hit using reprojection with the G2 on the OpenXR platform and I can see why this might not be the case for the Index on Steam. There have been several updates in the past few weeks though so hopefully this is moving in the right direction and my personal experience is great.

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Indeed. In case it wasn’t clear, I want to love my G2 so much. I’ve owned VR headsets since DK1 in 2013. In my opinion, the G2 is the first headset where the resolution is enough that image clarity is no longer a painfully obvious bottleneck in the VR experience. When the G2 is running at full res, I can quite easily make out all the small instruments and gauges. I don’t even have to think about image clarity anymore. It’s just driving me nuts that my rig is happy to push all those pixels… just only to a different headset with half the physical pixels :joy:

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That’s is basically the feeling I’m left with and for the same reasons.

Comparing WMR and SteamVR is also revealing to me how FS2020 on Xbox is not good for FS2020 on PC. 100% of Xbox are running AMD silicon, 85% of simmers are running NVidia silicon (Navigraph Survey). They made it clear in Q&A DLSS is not any better than their own AA algorithm (???). In other words, at least for this reason, FS2020 on Xbox is not good for PC because it is depriving the simmers from fully using their Video card hardware, only because the same type of hardware is not in the Xbox. Anyhow I’m derailing the topic.

PS: I didn’t plug my G2 back, so little time to do everything, but I’m curious about yours now tracking better than before and whether it is by sole virtue of the firmware and WMR/OXR updates, or if they changed the revision in the one they returned to you.

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We should have OpenXR -style implementation of motion smoothing instead of every HMD provider trying to write their own code.

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I might be wrong on this one, but OXR goal is unifying API, not implementation, so that applications can use a single set of functions to interact with various HMDs, but each HMD strength resides in the implementation differences. Motion Smoothing in OXR is not only not what OXR is meant for, but this would defeat the purpose.

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Who else beside you should decide this?

And what is so frustrating on a technology that we hadn’t even dreamed of two years ago? What do you need to be satisfied?

I enjoy flying in VR day by day and I am very excited about the things to come.

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I enjoy it too, and I can’t wait to know what is this new Vive product(s) they are about to announce!

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I read that’s it will be a couple of new vive headsets. Hoping for the best also.

I liked your analysis and have felt the same way about the G2. Decent hardware and low-rent software. I didn’t realize the drivers weren’t using the NV 3xxx hardware as intended, makes sense though.

It has gotten better being able to run 22.5 + 3, but it shouldn’t have to. I should be able to get 45+1 based on 2D performance.