That should work. Display Port versions are supposed to be backwards compatible. Is there an option in PiTools to let you reduce refresh rate to 75 Hz? I have a 980Ti with the same DP limitation. I sure hope there isn’t a problem which prevents me from using my headset (in a few months, when it arrives).
@Sean.Huang, have you tested this?
I really hope so. I have a 980 ti as well
Doc what gpu do tou have?
I found if you have red usb ports(high speed) be sure to use one of them
According to this Red ones are Not special high speed ports but always Provide Power for charging.
Either way ut seems to yeild better results. Though my gigabyte board has 0 of them & works fine.
Thanks for the correction. 
I have a MSI AMD R9 390 8GB
I have used the red USB port on my Gigabyte board with USB 2.0.
Updated the chipset drivers and VGA drivers but still not connected.
I have not found settings in PiTool to reduce to 75Hz.
The problem with display port I see is that DP1.2 can not deliver the amount of pixels needed for the Pimax to work.
It says in the small booklet that comes with the HMD that DP1.4 is minimum specs.
That is most unfortunate. 
Several people have 980Tis, like me. It’s roughly the equivalent of a 1070, so I (like others) assumed it would work with the headset.
The headset though should still connect at least. If your mobo has integrated graphics you may need to disable it in the bios.
I don’t see how DP 1.2 will support the Pimax. The specs are too low to meet resolution/refresh/bandwidth demand. This isn’t just a question of if a card is fast enough, its not able to meet what the Pimax is requiring as input signal.
17.28Gbit/s vs 32.4Gb/s bandwidth.
As far as I can tell 2560x1440x2@90hz requires higher than 17.28Gb/s
True, but if the refresh rate is lowered, it should be able to work. Pimax has indicated that they might support 60 and 72 Hz refresh rates. That should enable DP 1.2 to work, since 75 Hz and lower should fit the available bandwidth.
Yea, those features are not in yet but maybe possible? Don’t know enough about how they communicate but at reduced refresh it should be within bandwidth capability.
I have had minor success on my r9 390. Really simple games like Eve Gunjack runs well but this could run on android(pretty stable around 80 on 8k)
Distance on small fov works well.
War Robots VR tanks with ghosting & other jitters. Just not reccommended.
sounds like a per case grey area then… unsure if reduced fov reduces bandwith still or if its sort of fake reduction and only reduces rendering res? no idea if other factors still come into play to approve accepting the signal?
so how about colours , do we have any changes in new PiTool?
It was definitely interesting @Ludiks with his 1060 6g inspired me to try.
But the r9 390 is only rated for qhd gaming & we need 4k gaming. So yeah R9 390 a no go overal.
I did more playing last night, attempted to use my phone as poor mans lux meter and compare when connecting via different usb ports but readings are quite low so wasn’t getting anything useful.
Also noticed a brightness slider in bigscreen, put that on max and and have to say I’m still feeling it seems a bit better than I’ve seen during the past few days.
I’ve just gone into steamvr home now and I am absolutely certain now it is brighter than it used to be! no idea why yet? .90 or my pc?
Either way the main thing I was still disappointed with colour/brightness… I’m less disappointed with today 
your eyes/brain have adapted 
Quite possibly, even the small amount of visible SDE is starting to disappear for me at the moment. Clearly getting PiEyes 
I did a rollback to .84 and brightness looked the same, but pixel quality wasn’t as nice (and I did check all settings pitool/steamvr), went back to .90 and all nice and clear.
please compare this reference video on your monitor and on 5k+ bigscreen - YouTube
edit : and then between pitools versions
Maybe you’ve had a Mileckey transition…
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