Resolved MBP and Dual 30" Displays.

[eyoungren]

So, reference point.

The A1306 came today and I promptly discovered that I had the ports of my KVM backwards. Meaning that this specific KVM switch only supports ONE 30" Cinema Display! I so hate it when I screw myself by being wrong.

Anyway, short of swapping the display cable back and forth between Macs there's no way this is going to work. So, I found another KVM.

IOGEAR GCS1642 is a DualView, Dual-Link KVM. I found one on eBay for $29.95 with free shipping. Vendor says it's good, pulled from a working environment. Only what is included in the pictures. So, I get the switch and no power cable. Found a power cable for $19 plus shipping for this model KVM. So, together, about $56 after taxes. Pretty good I think. I could have done cheaper with the cable, but I've blown parts before with the wrong cable and didn't want to take a chance here.

USB 3.0 to Ethernet adapter is due in on Saturday the 21st.

Now, I should have everything. And if it doesn't work…that's it. I have no more money to throw at this.

 

[eyoungren]

OK. The gigabit USB<>Ethernet adapter arrived today and functions as advertised. So, I know that part works. Pulled down over 500mbps on a speed test.

EDIT: For whatever reason it shows as a Thunderbolt adapter. Whatever, it works!
EDIT2: Ahh, now it shows correctly!

 

[Amethyst1]

Have you received the new KVM yet?

 

[eyoungren]

Have you received the new KVM yet?

I need the cord though, otherwise it'll sit.

 

[eyoungren]

Have you received the new KVM yet?

It's in Phoenix now. Delivery by tomorrow.

 

[eyoungren]

KVM has arrived. As expected, it did NOT include a power cord. So glad I found one and ordered it. It arrived at the same time as the KVM. I've tested it and the KVM lights and makes beeps when I switch between computers and mode. The KVM did not fry when I plugged it in.

OK, so will be putting this together later tonight. Taking the opportunity to organize the area where the cable box and the work MBP sit. Will report back.

PS. USB>Ethernet adapter seems to work better (to me) than the TB>Ethernet adapter. I find that interesting, but maybe it's just perception, IDK.

 

[eyoungren]

OK. The result: FAIL!

New KVM works just fine. New A1306 works just fine too. The 2015 MBP with the Iris GPU simply will NOT drive two 30 inch Cinema Displays. I tried multiple combinations of powered hub and on board power. Nothing. Every time the second A1306 is plugged into USB power the Mac drops a power warning - even when the hub is powering the device. The Iris just cannot handle it.

OTOH, I got the sideboard cleaned up.

 

[Needleroozer]

OK. The result: FAIL!

New KVM works just fine. New A1306 works just fine too. The 2015 MBP with the Iris GPU simply will NOT drive two 30 inch Cinema Displays. I tried multiple combinations of powered hub and on board power. Nothing. Every time the second A1306 is plugged into USB power the Mac drops a power warning - even when the hub is powering the device. The Iris just cannot handle it.

OTOH, I got the sideboard cleaned up.

That’s unfortunate - it seems like the Iris Pro 5200 should be able to handle up to three monitors, according to the Intel spec.

Intel® Core™ i7-4770HQ Processor (6M Cache, up to 3.40 GHz) - Product Specifications | Intel

Intel® Core™ i7-4770HQ Processor (6M Cache, up to 3.40 GHz) quick reference with specifications, features, and technologies.

ark.intel.com

Just to make sure - are your USB hubs externally powered (i.e. from their own power bricks)?
You could also try plugging the A1306 USB plugs into iPhone chargers so that they are totally independent of the MacBook’s USB subsystem.

Edit: I just went back and read through your previous posts; sounds like your extra USB hub is indeed powered. I would still try an alternate USB power source, though.

 

[eyoungren]

That’s unfortunate - it seems like the Iris Pro 5200 should be able to handle up to three monitors, according to the Intel spec.

Intel® Core™ i7-4770HQ Processor (6M Cache, up to 3.40 GHz) - Product Specifications | Intel

Intel® Core™ i7-4770HQ Processor (6M Cache, up to 3.40 GHz) quick reference with specifications, features, and technologies.

ark.intel.com

Just to make sure - are your USB hubs externally powered (i.e. from their own power bricks)?
You could also try plugging the A1306 USB plugs into iPhone chargers so that they are totally independent of the MacBook’s USB subsystem.

Edit: I just went back and read through your previous posts; sounds like your extra USB hub is indeed powered. I would still try an alternate USB power source, though.

If I try that, it'll be this weekend. My problem is (if it works) I've got enough plugged in already*. Trying to find two more additional plugs will be a real pain.

*-1 Mac Pro, two Mac Minis, 1 G4, 1 G3, two 30" CDs, two 24" CDs, 1 20" CD, 1 HDTV, 1 soundbar, 1 cablebox, 1 set of powered speakers, 1 NAS, 3 external hard drives, 1 modem, 1 router, 1 LTE femtocell, 1 Airport Extreme, two switches, 1 Thinkpad, 1 charging station for phones/tablets, 1 printer, one lamp and two powered USB hubs.

 

[Amethyst1]

The 2015 MBP with the Iris GPU simply will NOT drive two 30 inch Cinema Displays.

I'm so sorry to hear that after having talked you into embarking on this adventure. This must be due to the A1306 then, since I had the Iris Pro 5200 drive two 3840×2160 displays at 60 Hz just fine (Late 2013 15" rMBP running Mavericks).

 

[eyoungren]

I'm so sorry to hear that after having talked you into embarking on this adventure. This must be due to the A1306 then, since I had the Iris Pro 5200 drive two 3840×2160 displays at 60 Hz just fine (Late 2013 15" rMBP running Mavericks).

Well, I will try the suggestion to use two iPhone chargers and see what happens. I don't have a lot of hope for that, but who knows.

 

[eyoungren]

So, I futzed with this today. The KVM is sending signal and I had no power complaints when I plugged in both adapters to USB power chargers.

I suspect then that the new A1306 may be bad. I don't have another 30" display to test with and I'm not messing with any more cords. I'm also out of money.

So, if anyone wants to give me a known good A1306 (or equivalent, PM me). I can afford shipping - I just do not have another $50+ to drop right now.

 

[eyoungren]

New A1306 on the way, thank you to @Amethyst1.

It would seem the one I purchased recently is defective. We'll see what happens when the new one gets here.

 

[eyoungren]

OK. So, with the advice of using iPhone USB chargers it works!

But here's the bad news. Unless the third display is the laptop LCD, it will not drive three displays.

I have all three hooked up, the third display being HDMI to DVI. Worked.

But now. No.

 

[Amethyst1]

Woohoo

As for the three external displays thing: IIRC this is some kind of (artificial) limitation on macOS - even though the Intel GPU can drive three displays, one of them has to be the laptop's. You can (1) try if three externals work on Windows () or (2) get one of these USB DisplayLink gizmos and hook up the 23" ACD to that - that will give you three externals plus the laptop's LCD if you want. Performance using one of these usually isn't great though.

 

[eyoungren]

Woohoo

As for the three external displays thing: IIRC this is some kind of (artificial) limitation on macOS - even though the Intel GPU can drive three displays, one of them has to be the laptop's. You can (1) try if three externals work on Windows () or (2) get one of these USB DisplayLink gizmos and hook up the 23" ACD to that - that will give you three externals plus the laptop's LCD if you want. Performance using one of these usually isn't great though.

I have one USB port left (I can use the passthrough on the Moshi for my keyboard) so will probably try that. But not until there is money for it again - which I don't know when will happen.

Thank you though for making what I have possible. And thank you @Needleroozer for the idea of USB chargers.

 

[eyoungren]

So, it would appear that DisplayLink does not support monitor rotation or clamshell operation. Since my 24" Cinema Displays are vertical I need rotation and I have the work MBP in clamshell mode. So, adding that third monitor is not going to be possible until this changes.

On top of that, research indicates that Apple eliminated video over USB after OS X 13.6. There may be a way around that (by enabling a kext) but without clamshell and rotation it make the issue academic.

My original desire was both 30" Displays active on the work MBP and I now have what I want so I can't complain.

 

[Amethyst1]

So, adding that third monitor is not going to be possible until this changes.

You can always go down the „external graphics card in a Thunderbolt enclosure“ route. That’s what I did on my main Mac - I can now run 8 monitors (3 from the Mac itself, 5 from the external card).

(I better shut up now )

 

[eyoungren]

You can always go down the „external graphics card in a Thunderbolt enclosure“ route. That’s what I did on my main Mac - I can now run 8 monitors (3 from the Mac itself, 5 from the external card).

(I better shut up now )

Nah, this is good. I think at this point I have spent all I am going to spend on a work computer that is not mine. I am not a 'needs' person, meaning I usually just get what I want and if that happens to also meet what I need then great. Right now the work MBP has more than I need - and my boss is not going to cover any of the expenses above that.

And quite frankly - I just don't want to. If this were my Mac, I might do that, but it isn't.