DisplayPort 4K60 flashing

[alexwhittemore]

This is what's happening: 

 

That's over a DisplayPort connection, to a Dell P2415Q. It happened with multiple cables, a Surface Pro 4 with AND without a Surface Dock as the source, and ALSO a Zotac VR Go backpack PC (NVidia GTX1080). Both after fresh Windows 10 Creator's update installs, and completely updated drivers, graphics and otherwise. It only happens at 4k60 - any lower-bandwidth mode, no problem. This monitor only has an HDMI 1.4 input, so couldn't test HDMI end to end at 4k60.

Dell sent a replacement monitor, which did the same thing. I sent that back and bought a BenQ BL2711U. I like it more, but it still does the same thing. This monitor HAS HDMI 2.0, and best I can tell, the issue doesn't happen when the VR Go (with native HDMI 2.0 out) is the source, connected via HDMI 2.0. But with the Surface pro, connected on any MiniDP port (dock or chassis) to an HDMI 2.0 adapter (Club CAC-1170), issue persists. Connected via any MiniDP to DP cable Amazon sells, issue persists. Connected Zotac to display via any of the three DP to DP cables I own, issue persists.

If I move the entire damn setup into a different room, issue persists. 

 

There's literally a single MiniDP to DP cable on Amazon I haven't tried, which is this Accell cable https://www.amazon.com/gp/product/B00A7R9I22/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1. That one's on its way. The only such cable sold by Amazon that's actually listed on the DisplayPort website as certified. But of course, I don't hold out a lot of hope. Will report back. 

 

Literally the only variable I've tried with N as low as 2 is "source computers" - luckily, I've got 3 Surface Pro 4's in this house, so I'll try another one of those tonight. Will report back also.

Surely I'm not the only person here, but I've replaced literally every possible variable in the system other than the DisplayPort spec itself, most with at least 3 samples. Cables with like 10 or 12 samples. Has nobody else found this to be an impossibly persistent problem? The only thing I have yet to try is a completely different Mains supply grid, maybe I'll try that tonight.

I'm going absolutely insane.

[Glenwing]

4 minutes ago, alexwhittemore said:

This is what's happening: 

 

That's over a DisplayPort connection, to a Dell P2415Q. It happened with multiple cables, a Surface Pro 4 with AND without a Surface Dock as the source, and ALSO a Zotac VR Go backpack PC (NVidia GTX1080). Both after fresh Windows 10 Creator's update installs, and completely updated drivers, graphics and otherwise. It only happens at 4k60 - any lower-bandwidth mode, no problem. This monitor only has an HDMI 1.4 input, so couldn't test HDMI end to end at 4k60.

Dell sent a replacement monitor, which did the same thing. I sent that back and bought a BenQ BL2711U. I like it more, but it still does the same thing. This monitor HAS HDMI 2.0, and best I can tell, the issue doesn't happen when the VR Go (with native HDMI 2.0 out) is the source, connected via HDMI 2.0. But with the Surface pro, connected on any MiniDP port (dock or chassis) to an HDMI 2.0 adapter (Club CAC-1170), issue persists. Connected via any MiniDP to DP cable Amazon sells, issue persists. Connected Zotac to display via any of the three DP to DP cables I own, issue persists.

If I move the entire damn setup into a different room, issue persists. 

 

There's literally a single MiniDP to DP cable on Amazon I haven't tried, which is this Accell cable https://www.amazon.com/gp/product/B00A7R9I22/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1. That one's on its way. The only such cable sold by Amazon that's actually listed on the DisplayPort website as certified. But of course, I don't hold out a lot of hope. Will report back. 

 

Literally the only variable I've tried with N as low as 2 is "source computers" - luckily, I've got 3 Surface Pro 4's in this house, so I'll try another one of those tonight. Will report back also.

Surely I'm not the only person here, but I've replaced literally every possible variable in the system other than the DisplayPort spec itself, most with at least 3 samples. Cables with like 10 or 12 samples. Has nobody else found this to be an impossibly persistent problem? The only thing I have yet to try is a completely different Mains supply grid, maybe I'll try that tonight.

I'm going absolutely insane.

Well it is the classic symptom of a display connection losing sync, which happens when the cable cannot handle the signal. I'd try the Accell cable.

[Gamerguy207]

What version of the cable is it if it's old go out and buy a new one because old cables can't handle as much as new ones

[sazrocks]

As others have said this sounds like the cables cant handle the bandwidth. What cables have you tried?

[alexwhittemore]

18 minutes ago, Gamerguy207 said:

What version of the cable is it if it's old go out and buy a new one because old cables can't handle as much as new ones

I have literally bought, in the last week, 11 DP cables from Amazon, a couple HDMIs from Monoprice, a mini-to-dp adapter from Frys, a minidp to HDMI active adapter from Amazon, and that's all on top of the cables included with the two different models of display. Of course, two of those 11 aren't here yet, and one is the listed online certified cable. So we'll see tomorrow about that nail-in-the-cable-coffin.

 

As an additional test, I just plugged the monitor into a 2014MBP via DisplayPort. It doesn't flash black, but it DOES at least SEEM to drop frames with about the same profile of random timing. I don't have time just now to verify that HDMI from the same machine doesn't. 

[alexwhittemore]

On the way:

https://www.amazon.com/gp/product/B00A7R9I22/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B009NE77XM/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

 

Tested and failed:

https://www.amazon.com/gp/product/B017BQCUGW/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1 (w/ known working HDMI cables)

https://www.amazon.com/gp/product/B01N12FB0W/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B06XRTB2YW/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B06XBD1KCR/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B013PWQN1Y/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B00YONKZ72/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B0134V3KIA/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B00C7RJQPY/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1

 

And of course the MiniDP to DP cable that came with the Dells, and the DP to DP cable that came with the BenQ as well as another, with a passive mini-to-DP adapter from Fry's.

All of them claim 4k60 support except for the two "tested and failed" above minidp to HDMI male adapters that are actually only good to FHD - my bad not noticing.

 

At this point, if it's the cable, it's the electrical standard itself.

[alexwhittemore]

Update: Brought the display to my girlfriend's house, on the astonishingly tiny chance there's some kind of mains electrical noise issue in mine. Nope - still flashes like a banshee. Same profile of incidence too - worst shortly after a reboot, then gets better over time, and maybe comes back under periods of load. We'll see what the definitely-100%-for-sure-DP-certified cable holds, but I'm not holding out a ton of hope.

[alexwhittemore]

Update: Accell cable came in. It was doing great for a few minutes, then I restarted to give it the real test and... Nope. Flashes like hell.

DisplayPort Sucks.