Multiple Displays have problems with El Capitan

mharelick wrote:

... effect I am having is that when I look at both screens they look like a full desktop. I can move windows objects around them and even put a window so that

its split by the monitors. When I click on the green button in the top left of the screen to make a window full screen, the secondary display turns black. This works with safari or any screen.

In Yosemite I was able to make a window go full screen across the two displays. That functionality appears broken in El Capitan.

I bought this machine 4 days ago and initially installed El Capitan before doing anything else. There has not been a history of usage of this machine before that.

This is a completely different issue from the other posters.

Ever since Apple introduced fullscreen mode to applications (in Lion, I think), the behavior with two displays was the one you described (one wasted display). There were clamors against this for multiple displays users for years. Then Apple introduced the option "displays have separate spaces" (in Mavericks, I think) and I never looked back. Menu bars in both displays, easy to have applications in either, even full screen if you wanted. I haven't used the old mode in years, except to test an issue in another thread. Are you absolutely sure that you had a two-display-wide fullscreen application? I don't think this was ever possible.

Luis et al,

I have a View Sonic VA2223wm display attached to my 21.5" iMac (late 2015) via mini display-to-VGA adaptor which El Cap is not correctly recognizing its screen resolution. The View Sonic works wonderfully at 1920 x 1080 as I have used it for several years with my old black MacBook (10.7.5 connected via mini DVI-to-VGA) which is now going into retirement. Once I ported all of my info over to the new iMac and set the display up, I was getting a stretched screen and my resolution was limited in my display settings to a max of 1280 x 1024 in scaled mode. I have been searching to see if there were any driver updates or other options to resolve the issue but given all of these more significant discussions about displays not even working, I believe it is an inherent issue with El Cap and the external display driver not being developed fully.

My workaround at the moment is to operate in a lower resolution setting with the screen dimensions not fully fit (its either that or have a stretched screen in default mode).

Any thoughts on this, which seems a simpler but equally frustrating issue.

Not sure if it will help, but I believe that if you hold the option key when pressing the scaled option you may get extra possible resolutions. At least I get them with the external monitor I just tried.

I returned the mac mini since it was not capable of doing what I needed.

Here is a solution that seems to work. It may be a corrupted connection file at least for Macs that connect to the Apple 27" monitor.

While connected to the external monitor, go to System Preferences > Network then select the connection on the left.

Choose the way you connect to your monitor, e.g. Display Ethernet.

After selecting it, delete it by clicking the - button at the bottom left.

Next, Click on the + to add a new connection.

From the dropdown interface menu, select the way you connect to your monitor. E.g. Display Ethernet.

Click Apply. Restart to be sure.

Hope this helps....

MacBook Pro (Retina, 15-inch, Late 2013) connecting to 2 ViewSonic VA2446 SERIES Displays.

Thunderbolt to VGA- successful.

USB/ss USB through UV Plus 39 to DVI - bust.

Set-up was working until update on 10/28.

Attempted PRAM reset. Multiple restart configurations. Detect Displays options. All unsuccessful.

Any ideas?

Cut the Gordian knot: set up second display Thunderbolt to DVI.

What is "fireport"?

My latest submission through the Apple Feedback Assistant for those enrolled in the Beta program.

A symptom of me being human; should have been Thunderbolt.

Ok, so if I understand correctly, your monitors work if connected through Thunderbolt, but not with an USB device (UV+ 39).

Did you download the latest drivers? There seem to be drivers posted in October.

Thanks, Luis.

I am running a rMBP. Had two 32 inch monitors hooked up for years. Updated to the new system. It would only recognize one that was connected through the thunderbolt port. The one connected through the USB never worked again. I ran all the suggestions on the page and ultimately purchased a HDMI to Thunderbolt adaptor and got the second monitor to display. However, after running for a few hours, the computer begins to run so slowly that I am forced to unpaid the adaptor and wait about ten minutes before reestablishing the connection. It is extremely frustrating. I just would love to go back and use by HDMI to USB connection and get things the way they used to be. Any help would be appreciated

Did you download the latest drivers for your USB to HDMI adapter?

That sounds promising. Could you please provide a link. Thank you