
Retina Mac External display problem - sayhello
https://github.com/oyiptong/retinadisplayproblem
======
mbell
Just a guess:

The patterns in the examples seem to be horizontal, meaning the raw (pre
'cable encoding', usually 8b/10b) bit pattern of the display output would be
repetitive . It wouldn't be out of the question that a slightly improperly
electrically balanced or terminated output could cause signal integrity
issues, including ringing (voltage exceeds spec on rising / falling edges)
which could trigger safeguard circuitry in a display (shut it off).

~~~
sayhello
I don't have any electrical knowledge. care to elaborate?

Is that a problem with the cable, terminals on the devices, the mini-
displayport dongle or either?

The problem also only seems to occur on Retina Macbook Pro's

~~~
mbell
If my guess is correct, it would be a problem in the design of the output
transceiver circuit on the RMP's motherboard, assuming the cable and receiver
in the display are built to spec.

Could be an IC issue, could be the impedance control of the connector, could
be the impedance control of the traces on the circuit board, could be poorly
chosen passives, could be interference from nearby circuits, etc.

I wish I could give you a better answer but high speed signal integrity is one
of the most obtuse and most black art aspects of electronics design, there's a
fair amount of non-intuitive physics going on, e.g. signals going down a wire
don't just go, they 'ricochet' off impedance differences. It's far too large a
topic to treat in a HN comment and its whole system encompassing so 'what it
could be' is a large set.

These types of things are not uncommon in hardware development, especially
with high speed signaling. The interactivity of such systems can be high and
hard to predict fully at times.

EDIT: Simply put - display outputs scan top to bottom, left to right. The fact
that the pattern that triggers the issue appears to be horizontal means it
would occur in the raw bit stream of the output in a periodic way. That means
there is some low order frequency in the system caused by this pattern (maybe
it repeats every 500khz or something like that). If there is something in the
electronics of the output of the RMBp that resonates at that frequency (easier
than you think), then it could possibly cause the described failure.

~~~
jrockway
> It's far too large a topic to treat in a HN comment and its whole system
> encompassing so 'what it could be' is a large set.

This is a good start:

[http://en.wikipedia.org/wiki/Transmission_line](http://en.wikipedia.org/wiki/Transmission_line)

------
zoop
This works for me with my first gen 15" Retina. This also happened to me at
[https://optin.stopwatching.us/](https://optin.stopwatching.us/), and I
assumed it was exploiting some kind of bug with fullscreen for an intentional
effect. I am using an external 20" older generation Apple display.

~~~
sayhello
It wasn't intentional. I'm not on the team working on stopwatching.us, but I
had the issue and wanted to get to the bottom of this.

If you've got the bandwidth, could you please post your monitor model and/or
snap a video?

~~~
zoop
Apple Cinema Display ‪23-inch DVI‬ (1920 x 1200) connected through a DVI/DP
converter. It doesn't happen when I open the image in photoshop.

------
singular
Not experiencing this with a mid-2012 Mac Book Pro Retina hooked up to an
external display via an HDMI/DVI adapter.

I wonder if this is some strange prank designed to get people to look at a
screenshot of
[https://optin.stopwatching.us/](https://optin.stopwatching.us/), esp. given
the '1px reproduction' of this is entitled 'We are watching you!' If so, I
really, really don't get it :-S

~~~
sayhello
Not a troll. Actually, let me host another version of the page.

The reason it's got the "We are watching you!" is because i noticed the
problem while viewing
[https://optin.stopwatching.us/](https://optin.stopwatching.us/)

Edit: hosted here:
[https://people.mozilla.com/~oyiptong/retinadisplayproblem/](https://people.mozilla.com/~oyiptong/retinadisplayproblem/)

~~~
singular
Ah fair enough, that made me suspicious in particular as that title seemed
unrelated to the bug :-)

I wonder whether my HDMI -> DVI adapter is making a difference somehow?

------
brisance
How long before it takes effect? I don't see anything on my Retina MacBook Pro
with Thunderbolt Display.

    
    
      Model Name:	MacBook Pro
      Model Identifier:	MacBookPro10,1
      Processor Name:	Intel Core i7
      Processor Speed:	2.6 GHz
      Number of Processors:	1
      Total Number of Cores:	4
      L2 Cache (per Core):	256 KB
      L3 Cache:	6 MB
      Memory:	16 GB
      Boot ROM Version:	MBP101.00EE.B02
      SMC Version (system):	2.3f35
    
    

Thunderbolt Display:

    
    
      Vendor Name:	Apple Inc.
      Device Name:	Thunderbolt Display
      Vendor ID:	0x1
      Device ID:	0x8002
      Device Revision:	0x1
      UID:	0x0001000100508120
      Route String:	3
      Firmware Version:	22.2
      Port:
      Status:	Device connected
      Link Status:	0x2
      Port Micro Firmware Version:	0.0.21
      Cable Firmware Version:	0.1.18
      Cable Serial Number:	C4M2263005QDNWFAX
      Port:
      Status:	No device connected
      Link Status:	0x7
      Port Micro Firmware Version:	0.0.21

~~~
cmsj
I also can't reproduce it with the Thunderbolt Display.

Are the original reproducers of this all using minidisplayport adapters? Or
are some able to reproduce using the native HDMI port?

------
moraljto
off-topic: how does he/she get those vertical tabs in Firefox in that
screenshot?

[https://raw.github.com/oyiptong/retinadisplayproblem/master/...](https://raw.github.com/oyiptong/retinadisplayproblem/master/display_problem.png)

(warning: that is the picture that apparently breaks certain displays)

~~~
sayhello
That's Tree Style Tab, great for tab hoarders like me
[https://addons.mozilla.org/en-US/firefox/addon/tree-style-
ta...](https://addons.mozilla.org/en-US/firefox/addon/tree-style-tab/)

~~~
moraljto
awesome, thanks!

------
kunai
This must be exclusive to the Retina MacBook Pro, then, because my MacBook Air
doesn't show the same symptoms.

~~~
sayhello
So far, I've only been able to reproduce it on first-gen 15" Retina
MacbookPro's

~~~
jlgreco
For what little it is worth, it doesn't repro on chromebook pixels.

------
octo_t
I can't seem to reproduce, but I've got two monitors (VGA + HDMI)

~~~
safwanc
Same here. MacBookPro10,1 with two monitors connected (VGA + HDMI) and I can't
reproduce.

------
freshyill
I can't reproduce it using the latest update to the Retina 15" MBP and an iMac
in target display mode, connected via Thunderbolt.

------
haxxorfreak
I can't reproduce the issue on a first-gen MacBookPro10,1 2.3GHz connected to
an Apple Cinema Display 27" (over mini-DP)

Apple recently swapped my LG LCD panel to a new Samsung one for ghosting but
I'm in clamshell mode.

------
keesj
Can't reproduce. mid-2012 MBP Retina + Cinema Display 24"

------
stordoff
Unable to reproduce this on my first-gen rMBP 15" with an LG TV connected via
HDMI. Will try my external displays (Dell/HDMI; LG/VGA) tomorrow.

------
kogir
Can't reproduce with MacBookPro10,1 + 2x Mini-DP->Dual-Link DVI + 2x Dell
3007WFP on 10.8.4

------
fearlessleader
Can't Reproduce on my 15" retina with neither a dell nor a vizio tv over hdmi.

------
psteinweber
can reproduce with all examples incl. stopwatching.us with mid 2012 rmbp and
LG 23EN43 which is connected via thunderbolt to DVI adapter.

display shuts off immediately.

Was quite confused when opening stopwatching.us yesterday, thanks for pointing
it our here :)

------
faramarz
No problems for me.

    
    
      Retina, 13-inch, Late 2012 HDMI Out

------
dlazerka
It's funny to see how many Hacker News writers use Mac, the most closed
hardware+OS, most anti-hackish.

How about renaming HN to stand for Hipster News?

~~~
lazugod
A Mac is the only computer on which you can legally develop for all major
operating systems, including mobile.

How is that closed?

~~~
jrockway
Apple puts artificial restrictions on what tools you can use to write iPhone
apps, and Macs are that allowed tool, so OS X isn't closed?

That is literally the dumbest argument I've ever read on HN.

