How will be achieve Crystal 120Hz if is feeded by DP 1.4?

If Crystal total resolution is 5760×2880 at 120Hz, even more 160Hz, how can be feeded by DP 1.4 conexion that is not reach this amount of birrate?
Moreover with HDR…

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They will tell us “Tobii Transport”, but I have serious doubts.
On it’s surface it offers good compression, but not without trade-offs in latency and visual loss. I’d like to assume that it’ll be somewhere between straight PCVR and wireless. Of course it’s all very much speculation as it was only announced today that the eye tracking and Tobii has been enabled on the production models. Whether it works remains to be seen. I personally have been pushing for more info about the 12K because I don’t see - even with Tobii Transport - how they can push the 12Ks specs without two DP1.4 connections, which has been the supposed and even confirmed in the prototypes, but as of yet, not confirmed for the production models (as nothing is confirmed for that of course). I fear that until a GPU comes about with DP 2.0, VR will be bottlenecked - resulting in reliance on “tricks” like Tobii Transport - which in theory will work fine, but in practice will be like DSC - as we know DSC created many problems for many older GPUs and such. I suspect Tobii Transport will have it’s failings too. Maybe something as simple as limitations of the XR2 not being able to compress larger settings quickly enough to prevent latency. It’s a tough game.

Bandwidth matters more than ever with PCVR - that’s really the advantage that it offers! I’m afraid gimmicks like Tobii Transport will result in latency, stutter, and blur that will be as unacceptable. I would like to know if Tobii simply relies on the same methods of rendering that Aero’s dynamic foveated rendering offered through the VRS of Nvidia. Not only is that limited to Nvidia GPUs - it resulted in gains of only 10-25% with some pretty invasive settings. Not the “factors-of-two” that we need for 160hz Crystals and certainly not 120-200hz 12Ks. We’ll see over the next year - but if Pimax is listening - please don’t cheap out on the cables/interfaces for the 12K! They are important! I guess that’s the X-factor as it was the difference between the 8K and the 8KX. I want the 12K to skip that delineation and jump to the 12KX - or it will be another 2-3 years before a true 12K HMD becomes a reality.

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Why doubts? That resolution at 120hz is already possible on the 8KX. It just requires display stream compression.


The Revised 8kX is running 7680×2160 and even with the increased wider FoV compared to the Crystal does have a FW that is able to offer 120hz Native; if not mistaken without decreasing the FoV. This came out during the 3090.

They are in this case using DSC(Display Stream Compression).

The Crystal also has am XR2 processor as well then add Tobii Foveate Transport.

With 160hz we don’t have any details as of yet what it may require.

I think the Xtal 8k can for example do 120hz by reducing Resolution to 5k. @Djonko ?

I can confirm this, was very surprised tbh.


Because the Crystal is 160hz and otherwise has the same total display resolution as the 8KX. So Tobii will have to give a compression ratio that is 30% above DSC. Nevermind HDR though - the Crystal does NOT accept an HDR signal. It simply applies an “HDR algorithm”.

The 12K will require an astonishingly larger bandwidth: 2.5x times the bandwidth for the 8KX or the Crystal! (120.4M “sub-pixels” vs 49.7M “sub-pixels” for the Crystal or 8KX). That alone means we are probably not going to get above 90hz on the 12K even with 2xDP connections. Thus why I was arguing that a 12K without 2xDP1.4 is dead in the water. I’m sure Pimax realizes that, but the fact that they released the 12K as it was shows how they could try to offer something with great displays, but no bandwidth. It’d be like offering a 8K TV with a single HMDI 1.2 input…

By my back-of-the-envelope calculation the 200hz advertised for the 12K is probably only with small FOV setting, DSC on, 2xDP1.4 and Tobii Transport providing a 30% uplift. That’s a lot of things to require and ask for. Perhaps Tobii Transport will exceed our expectations?

The question asked, and my answer, were about 120hz. 8kx is higher total resolution that cryatal so I guess 160hz might be fine, maybe slightly increased compression or reduced FOV?

120hz should be totally fine, I think I saw it already (mostly tried 90hz).


Something with the Reality hnds like the Crystal perhaps more than jist Tobii Foveate Transport us pimax mentioned Hybrid Rendering using the XR2 to offload things.

So with these hmds they are more thank a regular vr hmd.

Good point. DP1.4 supports full 8k resolution at 60 hz (with 10 bit color though instead of 30 bit) and the Pimax 8k of course only has half of real 8k resolution so you should be able to pump that at 120 hz (again with 10 bit color)

160 hz will be more difficult though, not sure how to do that without even losing more on color depth for example.

I’m not sure I’m caring all that much about refresh rates Hz compared to actually getting higher framerates. Nah… of course I don’t want tearing, so understand the Hz importance. Just that, given the power of current day GPUs, I wonder how we could realistically drive Crystal - 12K resolutions at native with high game settings and have a nice experience… Doesn’t sound all that possible.

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Posted already stated fact. Sorry.

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