Does the Pimax 4K actually have a 3840 x 2160 x 60 hz native input?

Hi there, I signed up here because I am interested in this older model, and the newer 8K + ones with native 4K panels.

Can someone tell me, if their Pimax 4Ks actually accept 3840 x 2160 x 60 hz signals over HDMI?

I believe it must be upscaled inside the display from something lower to 4K, as HDMI 1.4b cables cannot sent 2160p60 in RGB, and must instead use chroma subsampling to reach 60hz, i.e. 4:2:0.

For my application, I need a native 4K display. Does anyone who own the Pimax 4K check the EDID to confirm? Using CRU or MonInfo.

Thanks so much!

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The original Pimax 4k model upscales from 2560×1440 to 3840×2160. It can also upscale from 1080p.

Unfortunately the p4k does not support native input. While it is not bad it does have bad ghosting with head movements.

The 8k+ upscales from 2560×1440 per eye to 3840×2160.

Only the 8kX model supports both Native & upscaling modes.

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Thanks. Can you tell me, are the two Pimax displays in the 8K+ individually addressable as 3840 x 2160 x 60 hz? I read somewhere that it uses a single cable (DisplayPort 1.4 ?) so I’m wondering how it manages to pass 2x 4K raw over the wire. Does it use RGB signaling or 4:2:0 or DSC maybe? I’d like to be able to push frames individually to each of the 8K+'s displays as if they were logically separate 4K displays. I seem to recall DP has two-display daisy chaining along a single wire. Two wires would of course be fine too.

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I believe you mean 8k-X. 8K+ only runs at 2x 2560x1440.

I believe the displays in the HMD are not accessible as the separate displays in Windows. You might be able to write an app for SteamVR and push the image to each eye through there (as any other VR app does), but it will be subject to the pre-lens warp.

AFAIK there is no documented way to write directly to the panels without any intervention from the Pimax software.

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The 8k+ uses an upscaler to upconvert the lower Resolution to 4k/eye in the headset after the cable. As far as we know the 8k & 8k+ cannot accept a 4k native per eye; even with less refresh.

The 8kX however can run Native or Upscale mode…

Sorry for the typo, ya I meant the 8KX. Before I order one, I just want to make 100% sure it can accept a single, independent 3840 x 2160 x 60 signal per eye. I’m also curious how this actually looks from an EDID perspective. Has anyone received an 8KX retail yet? I’m dying to get one…

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Oh wait, according to the kickstarter, it looks like 80hz is the default.

Problem is, 60hz is the standard for 360 degree video so it would be a pity if it can’t use 1:1 pulldown for video. I hope it’s not like the Rift CV1 where the headset is always locked at its default. I believe the Oculus Quest can run at both 60 and 72hz, which is more convenient.

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That question we would need a more answer from someone with deeper understanding of bridgechips.

Going by idea of Brainwarp fps bump trick (if/when gets implemented) in theory displays should possibly be able to feed 1 display at a time. But tbh on my side don’t know the hardware deep enough to answer this.

Maybe @risa2000 a fellow pimax user might have a better idea. @Sean.Huang or @Doman.Chen might have sometime & if needed ask tech team.

80hz was for the 8k.

Pimax headsets do have refresh setting options. Starting as low as 60hz.

For example

5k+
60, 7x & 90, 120*
*Small fov

Oh, that’s good news. I remember when Carmack wrote about VR video needing 60 hz modes on the Go / Rift S and Quest, in addition to their higher modes, it struck me as nonsensical that only the max refresh rate was available on the CV1. It’s not like they didn’t know back in 2016 that VR video was going to be a big part of their promotional material. And in some cases 60 hz is better for games, too, because 45 hz (90 / 2) has higher latency than 60 hz, and having an uneven latency (switching between 45 / 90 hz all the time) can be jarring for both gameplay and game animation.

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Indeed. Now just to note. The 120hz mode is also only available on the 5k+.

I’ve often wondered what 120 vs 90 would benefit resolution, indirectly.

I mean, your head is constantly moving, even if ever so slightly, so updating the pixels faster might induce your eyes to not focus on the pixels themselves but the image behind them. Even if what your eyes are tracking are stationary relative to your body, your head still wobbles and turns all the time so higher Hz might provide a bit better res.

Once the 8KX is available I’d love to take a look at its EDID. Does anyone have it? Is that considered private info? I mean, it’s not like anyone can’t see it just by plugging it in and opening up Custom Resolution Utility (CRU) or Monitor Info.

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No one has the 8kX as of yet since there still finalizing it. A prototype is being demoed at shows.

As for 120hz vs 90hz? A lot will also vary to degree with the individual. But yes the feel should be smoother motion.

8K-X AFAIK (but feel free to search the forum for the other details) runs at 75Hz at the moment (in the native 4K mode). Whether it supports the other refresh rates is unknown and even if it was known, I would not trust it until proven.

So if you really need to know and depend on it, then you better wait for the official release and for independent reviews.

Concerning the EDID, I am not even sure if there is one with Pimax.

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