iMac Pro with dual 5k displays?

[alwaysbeincontact]

HI,

Is anyone using a iMac Pro connected to dual LG 5k displays? I know it supports this feature. I have been using a 2016 MacBook Pro running dual LG 5k displays. I have had more problems than I had hoped and way too many hours with Apple support trying to fix the issues.

 

[Samuelsan2001]

If anything Apple can run them it’s the iMac pro, I wouldn’t expect any laptop to run dual 5k displays without issue myself that’s worse than running VR.

 

[alwaysbeincontact]

It runs fine, but the lack of Ram on the MacBook hurts it. The MacBook really needs 32 gig in my opinion.

 

[macduke]

It runs fine, but the lack of Ram on the MacBook hurts it. The MacBook really needs 32 gig in my opinion.

I think system RAM wouldn't impact display performance too much. Maybe VRAM but that's mostly for 3D textures and such.

 

[jdphoto]

I'm currently running that set up, have had it up and running for 2-3 months. Initially there were two issues, one kind of annoying (that has since been resolved), one trivial. The kind of annoying one was if I didn't use the computer within the past 24 hours or so, when I woke up the displays (the iMac wasn't set to sleep, but the displays were set to turn off after so many minutes in Energy Saver) one or two of the LG panels wouldn't wake up and I'd have to reboot to get them to come back. This issue was fixed though I believe in 10.13.4 as I haven't had it happen once since that update. The trivial one is one of the displays doesn't let me adjust the brightness of it. I'm guessing this is also on the MacOS side also. The brightness it is at though is indistinguishable from what I have my other two set at so it's not an issue. I just noticed it when I went to set it.

I have these all wall mounted next to each other, with cables all managed to be hidden and run down inside the wall. Have to say, best setup I've ever had, and the iMac Pro is a beast with my multimedia workflows.

Edit: Thought it could be useful to include my iMac Pro config: 10-core; 64GB RAM; Vega 64 GPU; 1TB SSD

 

[Somian]

I'm running the 2016 mbp with two 5k displays right now. I have the 4GB of video RAM and it runs well. According to iStat menus, video RAM usage is at 50%.

I'm looking into getting an iMac, because the constant noise of the macbook pro is a little annoying. The "normal" iMac can only run one of the 5k displays, however, and while i'm at it, i'd like to extend the setup to three displays.

I've had a mac pro 5,1 with three 4k displays before, but that was run by a GeForce 980ti.

Did anyone run the iMac pro in this setup? How does it "behave"?

 

[Glockworkorange]

HI,

Is anyone using a iMac Pro connected to dual LG 5k displays? I know it supports this feature. I have been using a 2016 MacBook Pro running dual LG 5k displays. I have had more problems than I had hoped and way too many hours with Apple support trying to fix the issues.

My 2017 iMac is connected to a single LG 5 K. Works great and would absolutely attach a second one if the Mac could drive it.

 

[Hitrate]

I'm running the 2016 mbp with two 5k displays right now. I have the 4GB of video RAM and it runs well. According to iStat menus, video RAM usage is at 50%.

I'm looking into getting an iMac, because the constant noise of the macbook pro is a little annoying. The "normal" iMac can only run one of the 5k displays, however, and while i'm at it, i'd like to extend the setup to three displays.

I've had a mac pro 5,1 with three 4k displays before, but that was run by a GeForce 980ti.

Did anyone run the iMac pro in this setup? How does it "behave"?

Sounds like you need a Mac Pro mate as far as i've read imac pro behave just fine for what you need also

 

[Somian]

Ok, I did it. Got my iMac pro with a Vega 64 today Just the fact that it's possible to open Exposé buttery smooth with a ton of apps open is great. My 15" MacBook Pro always struggled with that with the two displays connected. According to iStat menus, when just doing some desktop things, it uses about 2 GB of video RAM, so there's a lot of room.

A little thing that bugs me about the solution is that, even though the iMac (and in theory the LG displays) have ambient light sensors, I have to use the keyboard to manually adjust each of the monitors after clicking on the desktop.

Is there a solution to just have all three monitors (built-in and the two LG monitors) to sync their brightness?

 

[blackmondo]

Thanks everyone for the info, there's not much commentary out there on how well a triple 5k display iMac Pro setup runs. I bought an 8-core iMac Pro myself this week, as one of our stores in Australia was clearing stock of the 8-core base model for $5999 AUD - almost 18% off the usual $7299 AUD price. I may regret this slightly if Apple update the iMac Pro soon, but there's also a chance they'll drop the iMac Pro altogether.

My experience with this setup so far has been amazing. My previous setup was a 16 inch i9 MacBook Pro 4GB 5500M model (the highest non BTO model) running 2 LG 5K displays. Even though the new 16 inch MBPs are very capable machines, this iMac Pro feels like the first Mac I've owned that can adequately drive 5K displays without constant fan noise and intermittent throttling. Everything is smooth as butter, and in a couple of days use I've never seen the computer struggle at all, and it's whisper-quiet even under load.

What's interesting is that the single core GeekBench scores for the i9 16inch MBP and the 8-core iMac Pro are basically the same, but in general use this setup is just miles better. The extra 16GB RAM, Vega GPU and cooling system also play a big part in making this setup so much smoother.

I'm really impressed, as this thing is driving a LOT of pixels. Makes me hope that Apple don't actually kill the iMac Pro model in general, as the only other machine that can drive 3x 5K displays is a Mac Pro, and then you need to buy an extra 5K display (and you currently can't get the LG 5K anyway).

 

[pldelisle]

as the only other machine that can drive 3x 5K displays is a Mac Pro

The iMac 2020 can drive its own 5K display + 2 6K Pro XDR displays with Radeon Pro 5700 and Radeon Pro 5700XT.

 

[blackmondo]

The iMac 2020 can drive its own 5K display + 2 6K Pro XDR displays with Radeon Pro 5700 and Radeon Pro 5700XT.

Ah yes, fair call.

But it can't drive two external 5K displays because it only has two thunderbolt ports (one bus), and the LG Ultrafine 5K display doesn't support DSC over TB3. Since I already had two LG 5Ks, this was by far the cheapest way for me to get that many pixels - a 2020 iMac with two Pro Display XDRs would be almost a $20,000AUD spend.

 

[pldelisle]

Ah yes, fair call.

But it can't drive two external 5K displays because it only has two thunderbolt ports (one bus), and the LG Ultrafine 5K display doesn't support DSC over TB3. Since I already had two LG 5Ks, this was by far the cheapest way for me to get that many pixels - a 2020 iMac with two Pro Display XDRs would be almost a $20,000AUD spend.

Seems it can but only a 8bit, so millions of colors instead of 1 billion. But yeah you lose the beauty of the 5K LG display.

AMD Radeon Pro 5300 and AMD Radeon Pro 5500 XT
You can connect up to one 6K display or two 5K or 4K displays in these configurations:

• One 6K display with resolutions of 6016 x 3384 10bpc @ 60Hz
• One 5K display with a resolution of 5120 x 2880 10bpc @ 60Hz
• Two 5K displays with resolutions of 5120 x 2880 8bpc @ 60Hz
• Two 4K displays with resolutions of 3840x2160 10bpc @ 60Hz or 4096x2304 8 bpc @ 60Hz

AMD Radeon Pro 5700 and AMD Radeon Pro 5700 XT
You can connect up to two 6K, 5K, or 4K displays in these configurations:

• Two 6K displays with resolutions of 6016 x 3384 10bpc @ 60Hz
• One 5K display with resolution of 5120 x 2880 10bpc @ 60Hz
• Two 5K displays with resolutions of 5120 x 2880 8bpc @ 60Hz
• Two 4K displays with resolutions of 3840x2160 10bpc @ 60Hz or 4096x2304 8 bpc @ 60Hz

 

[blackmondo]

Ah interesting, that spec isn't listed on the main or store pages, but it is here: https://support.apple.com/en-us/HT211281.

Would be interesting to hear how the standard iMac 2020 runs with 2 x 5K displays as well, and if fans/cooling are as good in particular. The iMac Pro is one of the quietest Macs I've ever owned, and I didn't pay much more than the equivalent specced up iMac 2020, so I'm still really happy with that.

It'll be great one day when Thunderbolt / USB and high res monitors just work at their highest res / bit depth without any of these exceptions. Perhaps Apple Silicon / USB4 is when that becomes a reality It's been a long transition...

 

[pldelisle]

It'll be great one day when Thunderbolt / USB and high res monitors just work at their highest res / bit depth without any of these exceptions. Perhaps Apple Silicon / USB4 is when that becomes a reality It's been a long transition...

Totally agree.

But Thunderbolt will be always better than USB. Apple Silicon will have Thunderbolt 3/4 implementation built-in.

 

[blackmondo]

But Thunderbolt will be always better than USB. Apple Silicon will have Thunderbolt 3/4 implementation built-in.

I thought I read that USB4 was essentially going to be merged with Thunderbolt 4 to remove the confusion. But now I just read that TB4 is no faster, and USB4 can potentially be a gimped version of TB4 depending on vendor implementation. Struggling to see how this is any better than what we currently have! The USB-IF ... ugh.

So you're right, TB4 will generally better than USB4. This is so confusing even for tech enthusiasts, so how do non-enthusiasts get their heads around it? What a mess.

At least Apple will always use the best version of the USB ports!