Connecting A Display To Two Computers

EDLIU

macrumors regular
Original poster
Oct 20, 2015
168
1
I have an ext. Samsung Curved Monitor that supports mDP and HDMI.

What will happen if I connect the display to two computers using the mDP and HDMI port simultaneously.

Thanks.
 

iMacDragon

macrumors 68000
Oct 18, 2008
1,712
283
UK
generally speaking, monitor will have some way of switching inputs, and will usually automatically switch to most recent turned on. Some monitors can display multiple inputs side by side or picture in picture.
 
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dwig

macrumors 6502a
Jan 4, 2015
659
242
Key West FL
...and will usually automatically switch to most recent turned on....
In my experience, it is always the other way around. When auto-switching is enabled, the monitor will switch to the first signal is detects and will stay on that input even if a new signal appears on another input. It will switch to the second signal only when manually switched or when the first is disconnected.

I use my old Dell 23" monitor with two computers via two of its 3 inputs. It is normally set to auto-select, but occasionally I need to switch manually when using both devices.
 

EDLIU

macrumors regular
Original poster
Oct 20, 2015
168
1
I use my old Dell 23" monitor with two computers via two of its 3 inputs. It is normally set to auto-select, but occasionally I need to switch manually when using both devices.
Can you share with us why you want to connect two computers to one display?

Thanks.
 

theluggage

macrumors 601
Jul 29, 2011
4,137
2,829
Can you share with us why you want to connect two computers to one display?
Maybe you have two computers and only one display (or only space for one display on the desktop)? Or a games console?

Obviously you can't use both at once, but you can avoid having to dive around the back of the display and re-plug cables every time you switch (unless you really like playing fit-the-trapezoidal-peg-in-the-square hole blindfold).

Or, maybe (like me) you've got two or more displays - in which case one can serve a dual purpose as a secondary display for your main system when you're only using that, or the display for your second computer when needed.

For a long time, I had a Mac Pro 1.1 (and later a Hackintosh) with a coupe of large displays as my 'home' system and a MacBook Pro as a 'work' system that commuted backwards and forwards to the office. When I was doing "day job" work at home I'd use one of the displays hooked up to the MBP. For non-day-job work I'd use the Mac Pro with dual displays.

Currently I've got an iMac and two external 'secondary' displays, normally with an extended desktop across all 3, but each external display also has various other cables plugged in to accommodate a home server (only needs a display when I'm configuring or troubleshooting it), a former Hackintosh now running Linux, my old MacBook Pro and a couple of Raspberry Pis that I sometimes mess around with.

My mouse can be paired with 3 computers, and switch between them at the touch of a button.
I've also got a wireless keyboard which can be paired with 3 systems and switch at the touch of button, that I can use if I'm 'multi machining'. Or, with 2-3 displays and 2-3 computers in play, there's a great bit of cross-platform software called "Synergy" that lets you share a keyboard and mouse between all 3.
 

EDLIU

macrumors regular
Original poster
Oct 20, 2015
168
1
I've only Dual Boot or Triple Boot my MBP and iMac. Maybe I can link my MBP and iMac to the ext. display now.:)

Thanks.
 

dwig

macrumors 6502a
Jan 4, 2015
659
242
Key West FL
Can you share with us why you want to connect two computers to one display?

Thanks.
I have two computers, one is my big Dell desktop and the other is my little Surface Go. The Go is used primarily as a "tablet" for media consumption and occasionally in a more "laptop" role while the desktop is used for "heavy lifting" (read: Photoshop, film scanning, ...). I have little space for my computer desk so I have only one large (23") monitor. Occasionally, it is advantageous to connect the Go to the large monitor. The include:
  • significant editing of the Go's configuration (new software installs, ...)
  • convenient continuation of some movie or such as I move around the house with the Go connected to the large display most of the time. It can be easily disconnected and taken to the kitchen for some other task without interrupting whatever I'm watching while having the benefit of the larger monitor when I return to my desk.
 

EDLIU

macrumors regular
Original poster
Oct 20, 2015
168
1
one is my big Dell desktop and the other is my little Surface Go. I have little space for my computer desk so I have only one large (23") monitor.
So what's the computer term for using multi computers with multi displays?

Thanks.
 

theluggage

macrumors 601
Jul 29, 2011
4,137
2,829
So what's the computer term for using multi computers with multi displays?
“Thursday.”

Seriously, not sure there is one but there are devices called “KVM switches” for switching a single Keyboard, Video and Mouse between multiple computers with a single switch. Not to be confused with Kernel Virtual Machine.
 

dwig

macrumors 6502a
Jan 4, 2015
659
242
Key West FL
So what's the computer term for using multi computers with multi displays?

Thanks.
Multiple computers with Multiple displays = 1 computer per display = "normal"

Multiple computers with a single display (and mouse & keyboard) is common in server rooms where there are a number of servers, but they only need to be interfaced with occasionally. I seen it used (actually used it myself) in software testing labs where a single tester needs to review an aspect of the software on a variety of different hardware configurations. Using a single monitor/keyboard/mouse set and a KVM switch, you can quickly switch to different computers without having to move around the room to different workstations.