KVM for MBP and Mac Pro (DVI and Mini Displayport)

February 23, 2013 6:20 AM

How can I best share a monitor, keyboard and Magic Trackpad between a Mac Pro and a MacBook Pro?

I've got a 2009 Mac Pro with a DVI out and just got a 2010 15" Macbook Pro with Mini Displayport. The Mac Pro is connected to an Asus 24" monitor's DVI port, but the monitor also has a VGA port (which I've read is not as "good" as DVI) and an HDMI port. I also have an Apple wired keyboard and a Bluetooth Magic Trackpad, as well as a regular Apple wired mouse around here somewhere.

My company gave me the MBP and wants me to get all my work stuff off my personal computer. I want to hook up the MBP so that I can leave it closed and use the same monitor and keyboard (and hopefully, the magic Track Pad) that I use for the desktop machine, switching back and forth during the day. The VGA KVM switch that the guy at Best Buy tried to sell me obviously won't work, at least not without a lot of adapters. I'm used to Apple stuff being easier to integrate than this.

What combination of switch and cables do I need? Price is a consideration, but not the most important one.

posted by Joleta to computers & internet (16 answers total)

Hook up the keyboard/trackpad to the laptop, install this on both systems, close laptop.

Cost: free (but there is a donate link if you feel so inclined)
posted by ijoyner at 7:13 AM on February 23

Synergy.
posted by bensherman at 8:13 AM on February 23

Depends on your eyesight and the distance of the monitor, you might not notice the analog nature and lower resolution of the VGA, but that's not something you could really know in advance. For whatever reason, I don't mind the artifacts caused by remote screen sharing, but the slight fuzziness of VGA drives me nuts.

If money is no object, a DVI KVM would work just fine. The tradeoff is that the monitor will have to "handshake" with whichever computer is in use, so switching is slow. However, once it switches the experience will be nearly as sharp and low-lag as being connected directly.

However, setting up Chicken (a VNC client) on your Mac Pro is free and makes it pretty trivial to switch back and forth. You may have to fiddle with the resolution on the MacBook Pro to get it to look right, and there'll always be some lag and visual artifacts because VNC is taking a screenshot and sending it over the network. Also note that the reason I recommend installing the client on the Mac Pro is because your company might not be happy with you enabling remote control on their machine. The only way this wouldn't work is if you have a "full tunnel" VPN that ferries all traffic to your company's servers. Then when you went to use your laptop, it would be pretty slow. I have not used Synergy.
posted by wnissen at 10:21 AM on February 23

You can get adapters so you can use the DisplayPort out. There are definitely DVI adapters, and there should be HDMI by now too. But DVI is simpler so I'd get a DisplayPort to DVI adapter and then a plain DVI to HDMI cable for the Pro (no adapter needed for that). Then use Synergy to share the keyboard and mouse after switching monitor inputs. No KVM required. You need an "active" adapter.
posted by snuffleupagus at 11:29 AM on February 23

I installed Synergy on both computers and hooked up the trackpad and keyboard to the MBP as ljoyner suggested. I set the MBP as the server and the MacPro as the client. I can control both screens with the trackpad and keyboard, moving the cursor between them, which is cool. However, when I close the MBP, I only see the screen of the MacPro on the monitor. I don't see how this arrangement will let me switch between seeing the MBP and the MacPro on the monitor.

I experimented by returning the trackpad and keyboard to the MacPro and setting it as the server, MBP as client. I can move the cursor to the MBP and use my full keyboard and trackpad, but I still need to look at the MBP's screen. I suppose that's better than nothing.

I'm going to investigate DVI KVM switches and hope they aren't too expensive. I know I'll need a Mini DisPlayport to DVI adapter for the MBP, about $30 at the Apple Store.
posted by Joleta at 7:22 AM on February 24

snuffleupagus: Can you explain a bit more about what plugs into where with that method?
posted by Joleta at 7:25 AM on February 24

Macbook mini display port into a display port/DVI active adapter, then a DVI cable into the DVI port on the monitor.

HDMI is in fact DVI + audio over one cable, so you can use a DVI--->HDMI cable from your Mac Pro to your monitor.

MiniDP to DVI active adapter
DVI to HDMI

Then run the synergy host on your Pro and the client on your MacBook. Use the monitors buttons to change inputs.
posted by snuffleupagus at 10:01 AM on February 24

(You'll have to pretend there are screens side by side or top to bottom for Synergy's purposes, and move the mouse "off screen" in the according direction to get the mouse/keyboard to talk to the other machine. Sounds weird, but you'll get used to it quick.)
posted by snuffleupagus at 4:51 PM on February 24

I've ordered the adapter and cable that snuffleupagus suggested. They should arrive on Wednesday. I'll post my success (or questions) in a few days.
posted by Joleta at 2:10 PM on February 25

I got the Mini DisplayPort to DVI adapter and the DVI to HDMI cable. I hooked them up as snuffaluoagus noted and got the monitor acting as a dual display extension of the MacBook. I couldn't figure out how to switch to viewing the desktop computer on the monitor, but when I disconnect the capable from the MacBook, leaving only the HDMI to DVI cable connecting the desktop to the monitor, the monitor says "DVI no signal."

I don't know what "Use the monitors buttons to change inputs" means.
posted by Joleta at 3:31 PM on February 27

Right--it says DVI no signal because you've disconnected the MBP from the DVI port. You need to make it look at the HDMI port, so it sees the signal coming from the Mac Pro.

Typically there's a button that changes inputs on the bezel of the monitor, or else a menu button and up/down and select buttons. Try pulling up the menu (aka OSD) and seeing if that's how it expects you to change inputs.

Or post the model of your Asus monitor, and I'll look it up.
posted by snuffleupagus at 3:46 PM on February 27

I'm almost there! I found the button on the monitor to switch between DVI and HDMI inputs. When I select DVI, I've got the MBP screen mirroring on the monitor, and I can use the keyboard and the bluetooth Magic Trackpad.

When I switch to the HDMI input, I see the desktop's screen and can move the mouse to it, but the keyboard is only typing on the MBP. I can't figure out how to get the keyboard to input to the desktop.
posted by Joleta at 4:34 PM on February 27

I figured it out. I need the keyboard plugged into the desktop because that's the server. The Magic Trackpad is actually connected to the desktop as well but by bluetooth. I believe everything is working correctly now. I should be able to disconnect the MBP from the monitor and take it with me to work elsewhere, then just hook it back up again when I get home, right?
posted by Joleta at 4:41 PM on February 27

Right. You may need to manually re-establish the Synergy connection. I haven't needed it in a couple years.
posted by snuffleupagus at 4:45 PM on February 27

Is there any problem with keeping the Synergy connection running all the time?
posted by Joleta at 4:49 PM on February 27

Well, the Synergy 'connection' won't be up and running while the computers aren't on the same network (your home network) even if you leave the program running. So when you get home you will probably need to re-establish the connection from the client (notebook) side, even if Synergy (the program) was left open on both machines.

There's nothing wrong with leaving the Synergy program running on the home mac; and it's probably OK to leave running on the macbook, too (although I tend to shut off any unneeded programs and services on a notebook while away from home for power saving and security reasons).
posted by snuffleupagus at 5:02 PM on February 27