Andreas, thanks again for assisting with this same process on the 
u2713HM. Works great.

Hi Andreas, could you upload the file for the HM version as well? 
Thanks!

Is there any chance you could walk me through this process or upload an 
appropriate file for a Dell U3011?

Having the exact same problem, and it's been a real nightmare. Would be 
eternally greatful!

I'm trying to figure it out on my own but I'm not sure where to look 
within the output from ioreg -l -w -0 > ioreg.txt

Thanks in advance for any help, appreciate it.

Wow, you're a champion for doing this. I've been sporadically trying to 
solve this for almost 2 years!

I managed to work as far as I could by replicating what I imagined your 
steps are – I got everything else figured out except the <data></data> 
tag.

My monitor is a Dell 2709W, and my ioreg -l is attached to this post as 
a .txt file. If you could take a look I'd really appreciate it – or let 
me know how you calculated the <data></data> tag contents so I can do it 
myself!

Thanks again, really appreciated.

Hi, Andreas,

Could you please help me to solve this problem for dell u2711 ?

Thank you very much

Hi Andreas,

Many, many thanks for the script. Like Alex I have been struggling with 
this problem ever since I got tried to use a mini-DP to DP cable to 
connect a Thunderbolt MBP to a U2410 monitor (about 2 years ago!). The 
script works fantastically for me.

Interestingly, the same monitor works fine with my original unibody MB 
(i.e. a true mini-DP port), and also works great with my new laptop in 
Windows, so I guess there's a bug in OS X somewhere in relation to 
Thunderbolt and these monitors.

Thanks again!

Dave

Dear Andreas,

There is some problems with run of this script. Probably i am quite 
stupid and did something wrong. Could you please help me with this. I 
attached terminal screen.

Dear Andreas,

I have tryed all ways to switch off my macbook display and run this 
script with only external display connected: switch it to sleeping mode, 
than to wake it up with keyboard, but still the terminal command to run 
the script doesn't work :(

Probably I am doing something wrong with typing in terminal window.
Should i put this script file in some specific folder?

I will be very appreciate to you if you could help to fix it in "ioreg 
-l" data

+-o AppleDisplay <class AppleDisplay, id 0x1000003be, re$
| | | | | | {
| | | | | | "IOClass" = "AppleDisplay"
| | | | | | "CFBundleIdentifier" = "com.apple.iokit.IOGraphicsF$
| | | | | | "IOProviderClass" = "IODisplayConnect"
| | | | | | "DisplayProductID" = 41047
| | | | | | "IODisplayEDID" = <00ffffffffffff0010ac57a04c353930$
| | | | | | "IODisplayPrefsKey" = "IOService:/AppleACPIPlatform$
| | | | | | "IOPowerManagement" = {"MaxPowerState"=3,"CurrentPo$
| | | | | | "IOProbeScore" = 2000
| | | | | | "IODisplayParameters" = {"bgsc"={"min"=0,"max"=6553$
| | | | | | "IOMatchCategory" = "IODefaultMatchCategory"
| | | | | | "AppleDisplayType" = 2
| | | | | | "IODisplayAttributes" = <676174760000000073676c6600$
| | | | | | "AppleSense" = 37119
| | | | | | "IODisplayConnectFlags" = <c4410000>
| | | | | | "DisplayVendorID" = 4268
| | | | | | "DisplaySerialNumber" = 809055564
| | | | | | }

Thank you

Hi Andreas,

Thanks for the RGB fix. I'm using the Dell U2713H on a new iMac.
Unfortunately there is a very serious problem with this display and I 
was wondering if you know if that's coming from Apple too:
After Hardware Calibration of the display (or using any other color 
profile besides "Standard") there is heavy green ghosting when I drag a 
window around. It is truly horrible.
Do you know if this is also connected to some Apple to Dell problem and 
how can it be fixed?

Thanks
Sebastian

I have Dell U2713H, and 15" rMBP and I filed a support ticket with Apple 
and they sent me a program called TimingSnoop to collect diagnostic 
output. That program seems to collect all EDID information, driver 
details and pretty much all display information. I sent them back the 
output but haven't heard back from them after that.

Forcing RGB seems to make some improvement, but the display is still 
very bad.  There is still some ghosting/fuzzy behavior and it does look 
like some sort of timing/refresh issue. Prior to forcing RGB, I was 
reducing the sharpness levels on the monitor all the way to zero and it 
seemed to make similar improvement.

Hi,

I just got the Dell U2713H monitor. I connected it with a macbook air 
mid 2011 model (Thunderbolt minidp) using a mini dp to mini dp cable.
I didn't have the YcBcR issue, although OSX system profile reports the 
monitor as "television".
The colors are fine and the Monitor color mode is in RGB as expected
The problem I have is a strange ghosting (probably an RTC overshoot 
issue) when moving windows or scrolling text!

I see Sebastian and Kr have also this specific problem, did you have any 
news from Dell or Apple support?
I have tried the EDID override thing but it doesn't seem to correct the 
"ghosting" issue. I have also tried connecting with several other dp 
cables but the issue is still there.

Has anyone tested this particular monitor with a standard DVI-D PC ?
This is the only test I have not done yet.

@andreas, yes I have already set the sharpness to 50 without which the 
display is unbearable but even with this workaround I still think that 
there is some ghosting/clarity issue.

@teowood
Apple closed my support ticket as a duplicate of another ticket and 
Unfortunately I'm not able to see the details in the other ticket.

I also want to test the display with a dual-link DVI connector but 
havent had a chance to do it and Dual Link DVI adapters are expensive

Well a pc with a good VGA card should be capable for a dual link DVI, no 
extra adapter needed. I am waiting for my alienware to arrive. I should 
do the test soon.
Meanwhile what i have noticed is that dropping the contrast from the 
default 50 to 40 or 39 almost makes the ghosting go...
I am thinking if i have to live with that or return the monitor :(

Hi All

New to the forum and had high hopes for this fix but alas on my Samsung 
SyncMaster SA350 it seems to have compounded the issue. Now the external 
monitor isn't recognised at all having applied the script.

I (foolishly) didn't backup the initial settings. Can someone tell me 
how to rollback?

Thanks in advance.

A quick thanks to Andreas and others you have contributed to this 
thread.  I recently purchased a U2713HM to use with my mid-2010 MBA and 
ran into the expected issues, first with getting the right cable to 
drive it at the full 2560x1440 resolution (mini-displayport to 
displayport is the cheapest solution), then with the issue of "off" 
colors and odd processing artifacts when it is being properly driven in 
YCbCr rather than RGB.  (I think some are not realizing the problem 
because the Mac will report that it is using RGB - you have to use the 
OSD on the monitor to discover what mode is it actually in.)

Anyway, using the attached file solved the problem completely and the 
display looks great.

- Mark

Many, many thanks for this Andreas!  My Dell U2410 worked beautifully on 
my 2006 MacBook Pro and via DVI-to-MiniDP on my new MBP retina, but the 
HDMI output looked lousy.  I had to take up a Thunderbolt port to use 
the monitor, but with this fix I can now use the HDMI and free up the TB 
port for a drive.

Thank you again!

John

Vitaliy,

I had the same problem. I suspect you are using 10.7 as I had the same 
error. Upgrading to OSX 10.8 allowed me to run the ruby with no error. I 
don't know ruby so it was easier for me to get the new OS instead.

Hi,
I have had the same issue as everyone else with my new Macbook Air 
connected via HDMI to a LG E2260 monitor.

I apologise, but I have absolutely no programming experience. I 
eventually found out how to "open terminal" but when I did enter the 
"ruby patch-edid.rb" into the terminal nothing happened. I suspect that 
I will need an external keyboard and mouse for this to work for the next 
step as I obviously cannot type anything with the macbook lid closed?

Could someone take a dummy through the procedure in simple steps?

Thankyou

I'm not sure if the problems that Katie and some others are reporting in 
this thread are the exact the same issue that we are all discussing 
about.

It is easy to confuse bad display resolution issue with the 
ghosting/fuzziness problem. If you need to drive really large resolution 
like 2440x1560 you need display port/mini-display/Dual Link DVI adapter, 
HDMI/SVGA adapters won't cut it and display wont look sharp with it

The original thread here is about Retina Macbook Pro models driving 
external display with 2440x1560 resolution or higher having two set of 
issues
1) Fuzziness/Ghosting issue on Dell U2713H/HM models
2) Macbook pro recognizing the external display as TV and hence using 
YCbCr instead of RGB mode.

AFAICT, Andreas script only forces RGB mode I don't think it solves the 
display quality problem, atleast not on my Dell U2713H.

FWIW, I removed the display override, tried the Apple Mini DisplayPort 
to Dual-Link DVI adapter to see if it improves the display, it doesn't. 
With Dual Link DVI adapter I do get the RGB mode automatically without 
the override but the display is bad to my eyes and My comparison here is 
the Apple Thunderbolt Display.

I have decided to return the dual LINK DVI adapter, and switch back to 
mini display port adapter. Now I'm not even using the YCbCr override, 
but adjusted the monitor settings (Uniformity Compensation Off, Smar 
Video Enhance off, sharpness set to zero) to get the same display 
quality.

Thanks so much!

This worked for me. I updated my macbook pro retina to 10.8.3 which 
still didnt work.

So downloaded the U2713H override and copied into the folder as stated, 
rebooted and perfect!

New dell ultrasharp u2713h working as it should.

Hi all,
I am a mac newbie and I am about ready to take it back due to this hdmi 
monitor thing (I have one more day to figure this problem out before I 
can take it back).  I have good color on it, and have downloaded OS X 
10.8.3.  Pictures, etc., look decent, but all text is still blurry. I 
have spent a couple of hours trying to get the display right...still 
nothing.  I am running hdmi-hdmi from my late 2012 mac mini (which I 
have read on other forums that this script works for).  My problem is, I 
don't understand mac coding and I can't get the script to run.  I 
download the script from above by saving the link to downloads.  I then 
open terminal, type in "ruby patch-edid.rb" and the only response I get 
is "command not found".  The process sounds simple as everyone says you 
just type that into the Terminal and a new folder will be created which 
you can then move to systems/library/displays/overide.  Is there 
something I am not doing right?  I really appreciate your help as I 
really like the new mac mini and want to keep it.

Hi,

Andreas - you are a genius. Many thanks.

Your script worked fine for my HP LP2475w - I've been searching for a 
fix for ages.

Apologies for the dum questions, I just came over to MAC OS with the 
purchase of a iMac 27.  I have a dell U2410 attached as a second monitor 
via mini-display to display port. Actually, the colors on the Dell seem 
fine, my problem is text.

Regarding the code you posted as universal fix for forcing external 
monitors to RGB: 1) What kind of file should I copy the code into 2) 
What should I name the file 3) where should I save it in order to run it 
3) How do I run it?

I tried copying the code into apple script editor and running it that 
way, but I get syntax errors.  I also tried just saving into a text file 
called patch-edid.rb and running from terminal, no joy.

Thanks for your help

Hi Andreas,

I use the U2713HM with a MBPr and have a problem with the screen 
flickering completely when scrolling certain websites (fine patterns 
seem to cause this behaviour, play.google.com is such an example, looks 
like a signal processing artefact). My display is also detected as a TV.

I'd like to apply your fix (thanks a lot for sharing your expertise!!!), 
but I use the DP audio output. As you fix removes some extensions, audio 
seems to be broken afterwards.

Is there a way to fix that problem without disabling DP audio?

Thanks in advance!

Update: Applied the fix, DP audio still works.

Update2: RGB works now, but annoying flickering with certain websites 
persists.

Does anyone know if this fix is necessary/works with OSX 10.6.8?

I have a new 27 inch iMac (2013 spec) on 10.8.3 and a Dell U2713H second 
monitor. I got the mini displayport to display port cable - and the Dell 
picture is clear at full 2500x1440 resolution BUT - the picture looks 
washed out and I cant get the same color balance as the apple.  I am not 
sure if this is just a difference in displays - or is the issue 
discussed in this thread:   When I go through the Dell screen settings - 
if I turn it to RGB - it goes awful - completely NG - so does that mean 
it is receiving YCbCr?
I then tried to follow instructions on this thread but am not familiar 
with terminal etc...

I downloaded "U2713H_U2713HM_Mac_EDID_override.zip" and put it on 
desktop
I opened them both and choose the one with U2713HM in it (and deleted 
the other)
I opened terminal and typed  "ruby patch-edid.rb".
But this came up with an error message ?

So I am stuck - but would greatly appreciate any help :)

Hi Andreas -

I have the U2713HM, which I have just had replaced due to the following 
issues:

- faint diagonal lines across the whole screen
- image noise when moving windows/scrolling pages
- strange flicker across whole screen if an image on my screen changes 
brightness quickly

The replacement monitor is suffering from the same problems.

I have tried using the Override files you provided but cant tell if this 
has changed anything. How do I see what colour space the monitor is 
using? I have gone into the monitors settings and it appears it is using 
YCbCr. But if I change that to RGB, the screen has a green and red tint 
applied.

The screen is connected to my Macbook Pro Retina via Mini DP to DP.

Any help much appreciated as this is driving me crazy and would really 
like not to have to send it back to Amazon again!

Thanks!

Dom

Hi Dom,

You can't change it manually: screen goes crazy if you do - I have the 
same setup exactly except I have the H instead of the HM.

You can use either the file at the very top of this page or the script a 
little way down. Either way should leave it that when you look at your 
monitor's settings, it will display RGB (after a reboot). After applying 
the script it should leave it perfect!

Using MBR with 10.8.3 and Dell U2713HM
I extracted the U2713H_U2713HM_Mac_EDID_override.zip and moved the 
contained folder into /System/Library/Displays/Overrides

I restarted the notebook with the connected U2713HM but this monitor 
stays black. Nothing to see… :-(

What I'am doing wrong?

OK, found the problem - my mistake. You have to set the Input Source at 
the monitor to DisplayPort manually... now it works perfect... thx 
Andreas :-)

I had to slightly modify the script for it to work with a Dell U3014. 
The EDID was cut off without an additionally "-w 0" parameter to the 
ioreg command.

Attached the updated script. Thanks. Works perfectly now :)

I've got the U241§3 on the non Retina Macbook Pro 2012 model and had 
loads of the issues most people mentioning. Colour being off, not 
looking sharp, basically looking worst than a cheap monitor! Thanks you 
so much for this, the script works perfect and the monitor now looks 
great.

This script doesn't seem to work with an hp pavilion 23bw. can you help 
on this one?

Thanks

YES YES YES! Worked a treat - shame it doesnt get rid of the ghosting on 
my DELL U2713H!

Thanks so much!

I'm executing script only with external monitor and got this

/System/Library/Displays/Overrides/patch-edid.rb:9: undefined method 
`[]' for nil:NilClass (NoMethodError)

what I'm doing bad?

Thank you so much for your solution. I was sick and tired with DELL 
U2713H changing settings on its own when connected to mac as a secondary 
display.
It was so frustrating to work with photographs in Adobe Lightroom and 
not seeing consistant color and tone, because display was tweeking it 
self for some reason.
I was going to sell it and get another one...
I did as you advised and now it doesn't tweek the color and tone and 
works consistently.

Thank you for your effort to figure this issue out and sharing it with 
the rest of the world. Appreciate it a lot!

Sergey.

I have an older 2011 MBP with thunderbolt, and a Dell U2713HM.
Currently connected via a mini -> display port, I dont see too much of a 
problem other than the dell looks vastly less sharp than I would expect 
for such a high res monitor even at 2560x1440. (Sharpness has to be ~75 
to look decent, any higher and I get halos, lower and it looks scaled)
Would this 'hack' help me? Most of the replys are from retnia based 
MBPs.

If I don't want to remove the extensions block, should I delete the 
following lines from your script?

puts "Number of extension blocks: #{bytes[126]}"
puts "removing extension block"
bytes = bytes[0..127]
bytes[126] = 0

bytes[127] = (0x100-(bytes[0..126].reduce(:+) % 256)) % 256


Is this correct? Will the checksum be recalculated correctly?

The script that was supposed to work on various models worked fine for 
me on the u3011, with the new u2413 I cannot get it to work properly. 
The sharpness and image is fixed but when editing in Premiere there is a 
purple box the fills the area that the video is being played. As soon as 
I stop playback it returns to normal. Sometimes I have a large purple 
box overlaying the screen thats about 80% the size of my screen. Tried 
for a screenshot, but this is caused by the monitor.

Videos I play in the browser also do this. Notice the overlay on just 
the video, it extends past the player slightly.