mavericks loses 2560x1440 resolution on Dell U2711

Should work fine, that's the one I use. To be precise, the trick is working on the thunderbolt port that's near the magsafe connector, not on the other one (maybe I didn't tried hard enought).

WAOW!! Thank you!! For a very weird reason when i plug it into the port near the magsafe it works fine!!

Thanks again so much!!

I'm glad it finaly works! Have you seen other thread about this problem?

We should definitly spread this solution. Could you do that?

I would be ok to do so but i have no idea how?

I assume this is not the only thread about this problem and you have probably gone throught many forums before to find this solution.

So it would be nice to go to the other forums and link to this thread, so when somebody is having this problem, it will be easier to find the solution.

I helped you, help the next one and the world will be a better place. And yes, sometimes I'm a f****ing hippie.

haha hopefully some people still are!!

Actually i didn't, went to the apple store to show the problem on the day after purchase and they found me the link to this thread and then just waited for an answer. Was about to go to genius bar to try to find a solution, been on the phone with Apple care so many times about this problem, you were the first one to find the answer!

So i will keep the link and if I ever se anyone asking about this I will pdefinitely provide the link!!

FWIW, the solution to your problem was posted in this thread back in Nov 9th, 2013 🙂

Hi, i had/have the same problem with my Dell U2711. We just upgraded our work computers to the new Mac Pro (late 2013) and began having this problem of the display showing at the max resolution of 1920x1080, not the 2560x1440 it should be. We were using HDMI 1.3 cable to the HDMI port of the monitor and nothing worked, so we bougth some HDMI to DVI-D cable and started to try some solutions.

So after many many many threads on forums and a lot of testing i found something that "works" and here's the solution: I downloaded SwitchResX and added a custom resolution with the following settings

The only problem is that we got the monitors running at 41Mhz and not the 60 it should be running at, and i can confirm this settings works absolutely fine via bootcamp on Windos 8.1, so the problem i think is Mavericks, limiting the HDMI output to fewer frames.

If i find a better solution i'll try to post it here.

Hello I found a solution that doesn't require to purchase any software.

I have a Dell U2711 and it was very frustrating not be able to use the full native resolution of the monitor.

When I upgraded to Mavericks, I had the same issue. I was able to easily fix this by simply pressing the option key when I clicked on "Scaled". This showed extra options including 2560x1440.

When I upgraded to Yosemite beta it was gone again. I tried everything including SwitchResX and nothing worked until I saw NestorC's post.

Here are the steps I followed to get it to work:

1. Download the trial version of SwitchResX, install it

2. Create a custom resolution as shown in the screenshot from NestorC

3. Restart system and select new available resolution. This give me 2 black lines on each side of the screen, so it still wasn't fixed.

4. Go to System Preferences again, now you should be able to see the 2560x1440 resolution as an option, click on it and voila

5. You can uninstall SwitchResX and the resolution will remain as an option. At least it did for me.

Hope this helps someone

On a Late 2013 rMBP, using TB-to-DP cable (from Monoprice), I get full native resolution.

http://imgur.com/I1pK0gE