What 2 x 4K 60Hz monitors work with 15 rMBP 2014-present and 2 x 4K with 5K iMac?

[cmm]

Hello

And by "work" I don't mean by what Apple promises (I was burned by Apple with the GUI problems from 10.10). I need to streamline my home computing environment now that I am mainly working inside VMs via Virtualbox locally and via VPN.

I'm deciding between a 5K iMac (with 64GB RAM and SSD, not that it should matter) or a 2014 to present 15 rMBP (16GB of ram and the dGPU).

I'm specifically interested in knowing the limits of the two machines I mentioned. I have many static (txt docs, PDFs, latex docs, sublime text/IDE and iterm3) windows open all day (not to mention various VMs with the same workflow stuff and matlab) as well as several chrome canary windows open.

My ideal would be going with the laptop (despite low RAM I have servers with much more that are easy enough to access) because I don't want a desktop workstation if and only if the 15 rMBP can handle two displays without getting the spin wheel of death and general lag when moving a window or doing some other banal action. If the 15 rMBP cannot handle two 4K's without hiccups, I'll go with a 5K iMac and 2 4K monitors. Despite the extra screen with the 5K iMac, I still prefer the laptop. Again, if and only if the laptop will be able to keep up with my workload.

If it matters, I prefer to run at 1440 HiDPi rather than 1080 but if 1440 causes strain and 1080 does not, I can concede. But 60 Hz is a must.

Finally, will I have any issues running a PCIe to 10 GbE adapter (this connects to my server and SSD RAID array). What is the recommended way to run this so there is no performance hit to neither the SSD RAID and the monitors?

There is so much info on these forums a doubt the various displays and it's confusing since a lot of people are reporting problems from more than a year back, when MST, 30 Hz and 10.10's horrible software support for GUI. Things have gotten better and now I'd like to make a move. I have several Dell P2715Qs at work on other machines and other people have the P2415Q among many others. I have no brand loyalties, just prefer a good value which the Dell P2x15Q is. But are the problems reported in the mega thread still an issue on 10.11 and newer hardware? Other sub $1,000 options to consider that give me what I want?

Thank you. Hopefully this thread helps many others and not just me.

 

[JTToft]

Finally, will I have any issues running a PCIe to 10 GbE adapter (this connects to my server and SSD RAID array).

- That I can answer. If you're thinking from Thunderbolt to 10 GbE, you'd be taking up one of the ports you would need for the monitors. So that adapter would need to have a second Thunderbolt port for daisy chaining. In addition, I'm not completely convinced 4K 60 Hz and 10 Gb Ethernet could run simultaneously within the 20 Gb available on the Thunderbolt port.

 

[cmm]

- That I can answer. If you're thinking from Thunderbolt to 10 GbE, you'd be taking up one of the ports you would need for the monitors. So that adapter would need to have a second Thunderbolt port for daisy chaining. In addition, I'm not completely convinced 4K 60 Hz and 10 Gb Ethernet could run simultaneously within the 20 Gb available on the Thunderbolt port.

Despite my disappointment, I mean this very much: Thank you. That sucks. It throws a big wrench in my plans. How much overhead does TB2 have?

I knew I needed to daisy chain it, I didn't think it would affect it more than overhead + ~10%. Do you have any idea the drain I'd experience? I could add one of my SSDs to my HDD array as caching and put the other 5 SDDs in a pure SSD array at work. I'm not sure what benchmarks to expect from a caching array and if it would be sufficiently low enough to get the benefit of an SSD cache but not overwhelm the TB2 channel. Any idea?

Does the current 5k iMac or 15 rMBP have HDMI 1.3? Are you able to run 60Hz on it?

Are these my only options at this point if I want to run 2 4K displays?

(1) get a cMP or nMP (nMP has 3 4K monitor support so I'm assuming it has at least that many TB2 ports and cMP has 4xPCIe2)

(2) Accept reduced amount of bandwidth with computer <--> 4K <--> 10GbE [1] Given my data, SSD caching would be a near-ideal use case but my hardware budget covers so I bought 6x1TB for home.

It seems I'm taking a gamble if I go with two 4K monitors, even if I accept (2) the monitor could have difficulties and the SSD cache may not deliver any extra performance over the HDD array due to sharing the lane with the 4K. In theory I could get two monitors and return one if I have any issues. But I want to get this done.

The way I see it is I have two choices: upgrade my late 2013 13 rMBP to a current 15 rMBP and buy a 5K iMac with 1 4K monitor each and use 1 keyboard for both devices. A bit clumsy but it can work. The second option is go with either the 5K iMac or 15 rMBP and use 1 4K monitor each. I'm really against having to maintain 3 workstations, one is enough (including my work workstation). The last option is go with the 15 rMBP, get 1 4K display for home and use it for its portability (I don't have to take it to work but if I go other places...).

It seems the most reasonable thing to do is work with only one external display. It's possible but not ideal. But I don't see another option. The most important thing is to not have any lag or spinning pinwheels. Would you agree? Or am I missing something (maybe the 5k iMac or current 15 rMBP HDMI is 2.0 and I can use that at 60Hz for one 4K display???)? Otherwise, I think I'll upgrade to a 2014 or current 15 rMBP model to keep as a backup and a 5K iMac with 1 4K display.

NB I have no desire to wait for an when Apple updates to TB3 and to see what TB3devices come available that are vastly overpriced.

Thanks again. I'd love to hear more about your experience. Any other things I should consider with a 10GbE adapter that is specific to OS X? I work with large datasets in an academic environment and haven't used OS X before for this kind of workload in any serious way. But my group is moving to OS X and VMs or containers when needed.

[1] My HDD array is connect via my Dell r710 in a 6x6Tb in raidz1 (I also have a z2 array for backups but speed is not important and of little concern for me on that array; I could run that over Ethernet and be happy). I can setup SSD caching to get some benefits of the SSD if it will make my 4K display work properly.

 

[JTToft]

You're welcome.
Below, I have omitted quoting and responding to the questions more specific to your intended setup which I don't know much about.

How much overhead does TB2 have?

- Can't say. But even within the 20 Gbps specification, I don't think you can have 4K 60 Hz and 10 GbE. 4K, to my knowledge, takes around 12-14 Gbps. So that leaves only 6-8 for Ethernet.

You may be interested in this article: http://www.anandtech.com/show/7049/intel-thunderbolt-2-everything-you-need-to-know

Does the current 5k iMac or 15 rMBP have HDMI 1.3? Are you able to run 60Hz on it?

- The iMac doesn't have HDMI at all, and the MacBook Pro has version 1.4 which can only do 4K 30 Hz. 60 Hz has to be via the Thunderbolt ports. Mac Pro is also HDMI 1.4.

Are these my only options at this point if I want to run 2 4K displays?

(1) get a cMP or nMP (nMP has 3 4K monitor support so I'm assuming it has at least that many TB2 ports and cMP has 4xPCIe2)

(2) Accept reduced amount of bandwidth with computer <--> 4K <--> 10GbE

- It would seem that way, yes. The Mac Pro should do everything with its six Thunderbolt 2 ports.

It seems the most reasonable thing to do is work with only one external display. It's possible but not ideal. But I don't see another option. The most important thing is to not have any lag or spinning pinwheels. Would you agree?

- It's certainly the safe option. Though I would estimate 2 x 4K should also be plenty smooth insofar as the monitors themselves are concerned. If anything is to suffer, I would expect it to be the Ethernet interface.


Another note: Late 2013 MacBook Pro in the 15" size with discrete graphics and newer can all run 2 x 4K at 60 Hz. The 2015 presumably better than Late 2013 and 2014.

 

[cmm]

Thanks for your reply and sorry for my lateness. Are you positive all 14 rMBPs from late 2013 to today can handle 2 4k displays? What do you mean by "[t]he 2014 [sic] presumably better than Late 2013 and 2014"? That is to say, in what ways are the newer 15 rMBPs "better" vis-a-vis powering 2 4k 60hz screens? Is there noticeable lag that does not exist in the newer model? Did any of the later 2013 15 rMBPs have two levels of discrete GPU? I know that OS X 10.10 was a disaster for 4k support but if the 2013 15 rMBP is running on 10.11, how does it compare with the current of 2014 15 rMBP model?

Are some 60Hz 4k displays better than others with their support for 4k on Apple? I really like the Dell P2415Q and Dell P2715Q (I have several at work) monitors but if another monitor lags less than the Dell models I listed here, I'd consider using it...

If I can get a definitive answer on this, I can then iron out exactly what I'm going to do.

Thank you!

 

[rdav]

Are you positive all 14 rMBPs from late 2013 to today can handle 2x 4k displays?

Only the high/spec rMBP(2014) includes a discrete GPU, [the GeForce 750m]. This will run a single external UHD[3840x2160] monitor. [https://support.apple.com/en-us/HT206587].

However, I've tested this configuration, and it struggles - The monitor occasionally flickers, the rMBP fans run high, and some applications stall. So I very much doubt that you will be able to run two of them from those laptops without problems, over time.

As for other options, have you considered the BenQ BL3201PT /?

Would be curious to know how others are doing with 2x UHD/4k monitors running off a recent iMac/27/Retina/2015/ (which can drive one 5k monitor via MST).

 

[campyguy]

Only the high/spec rMBP(2014) includes a discrete GPU, [the GeForce 750m]. This will run a single external UHD[3840x2160] monitor. [https://support.apple.com/en-us/HT206587].

However, I've tested this configuration, and it struggles - The monitor occasionally flickers, the rMBP fans run high, and some applications stall. So I very much doubt that you will be able to run two of them from those laptops without problems, over time.

As for other options, have you considered the BenQ BL3201PT /?

The BL3201PT is a pretty nice display - we have a few in my offices. It will be updated shortly, more in line with its 27 inch relation (BL2711U, with updated specs including HDMI 2.0) - also, which we have several in my offices. The BL3201PT is a nice piece of kit for production work - production as in CAD and modeling work.

More to the key point of my post, parroting what I've written in the thread about the P2715Q - two of which are on my desk right now, attached to my late-2013 15" dGPU rMBP. I'll echo what I wrote in that long thread- my rMBP drives two 27" Dell P2715Q displays at up to 4k @60Hz in either portrait or landscape mode (or in a combination of those displays modes) along with the internal display at full resolution. Apple's web page is not correct - I notified them months ago and they're sticking with their story.

What I will offer is that the COXOC-made Dell mDP>DP cables are not DP 1.2 compliant. DP's own website does not list COXOC among its certified vendors - I switched to Accell cables for my offices (53 Macs and PCs), and it was similar to turning on a switch. Computers running cooler, computers reading EDID information correctly without 3rd-party hacks (like SwitchResX, of which I own several licenses), no flickering/lagging/sleep issues. The Accell DP 1.2 cables carry more bandwidth as well - COXOC cables return power over Pin 20 (Google that...) and have zero documentation about their bandwidth-per-channel. No worries here - I had the same gripe as you did, and, now I don't. I don't understand - now - why some will drop $500 on a display and not get a decent $20 cable, it's like putting regular in my E550...

My personal late-2013 rMBP runs perfectly with my 2 Dell P2715 displays at home and BenQ BL2711U displays at the office. Cheers!

 

[rdav]

..More to the key point of my post, parroting what I've written in the thread.

Thanks, some interesting info, and from a super-user too. Will have to try those Accell cables. [Reference the B00A7R9I2M /B00A7R9I22 models]? It's certainly odd that the monitor manufacturers would try to cut costs in that area.

Somewhat off topic, but in your mob of Macs, do you happen to have any iMacs running 2x external 4k monitors? Presumably, if those rMBP models can manage it without complaint, then the iMac (2014 & 2015) should have no difficulty. Same with a single external 5k monitor, via MST.

 

[cmm]

Only the high/spec rMBP(2014) includes a discrete GPU, [the GeForce 750m]. This will run a single external UHD[3840x2160] monitor. [https://support.apple.com/en-us/HT206587].

However, I've tested this configuration, and it struggles - The monitor occasionally flickers, the rMBP fans run high, and some applications stall. So I very much doubt that you will be able to run two of them from those laptops without problems, over time.

As for other options, have you considered the BenQ BL3201PT /?

Would be curious to know how others are doing with 2x UHD/4k monitors running off a recent iMac/27/Retina/2015/ (which can drive one 5k monitor via MST).

This is what is so frustrating to me! Half of the people say it runs fine the other half says that it struggles. Indeed, I am inclined to agree with you because I've had issues with other Apple machines keeping up with the graphics when using external monitors.

Right now I am using a Thunderbolt 27" Apple display in a HiDPi mode thanks to SwitchResX. It looks good for reading text (which is mainly what I do) although I lose screen real estate with the vertical black bars. And at 1680x1050 (I think that's the res, don't quote me), it is too big for me...my hope is to get a monitor that can do 2560x1440 HiDPi

I can live with one external display but I need that external display to be able to work without struggling with my computer. Do you think the current 15 rMBP would be able to do that? Since I can't get two displays, I think what I will need to do is buy a 5k iMac as well and run an external display from there.

Why did you recommend the BenQ BL3201PH? I am looking at the P2715Q or P2415Q because of the text crispness that HiDPi offers and it is currently available at an attractive price. Can you be more specific about the struggles you faced when testing a UHD monitor? I don't understand why somebody would want a 34" monitor that isn't HiDPi.
[doublepost=1470229774][/doublepost]

The BL3201PT is a pretty nice display - we have a few in my offices. It will be updated shortly, more in line with its 27 inch relation (BL2711U, with updated specs including HDMI 2.0) - also, which we have several in my offices. The BL3201PT is a nice piece of kit for production work - production as in CAD and modeling work.

More to the key point of my post, parroting what I've written in the thread about the P2715Q - two of which are on my desk right now, attached to my late-2013 15" dGPU rMBP. I'll echo what I wrote in that long thread- my rMBP drives two 27" Dell P2715Q displays at up to 4k @60Hz in either portrait or landscape mode (or in a combination of those displays modes) along with the internal display at full resolution. Apple's web page is not correct - I notified them months ago and they're sticking with their story.

What I will offer is that the COXOC-made Dell mDP>DP cables are not DP 1.2 compliant. DP's own website does not list COXOC among its certified vendors - I switched to Accell cables for my offices (53 Macs and PCs), and it was similar to turning on a switch. Computers running cooler, computers reading EDID information correctly without 3rd-party hacks (like SwitchResX, of which I own several licenses), no flickering/lagging/sleep issues. The Accell DP 1.2 cables carry more bandwidth as well - COXOC cables return power over Pin 20 (Google that...) and have zero documentation about their bandwidth-per-channel. No worries here - I had the same gripe as you did, and, now I don't. I don't understand - now - why some will drop $500 on a display and not get a decent $20 cable, it's like putting regular in my E550...

My personal late-2013 rMBP runs perfectly with my 2 Dell P2715 displays at home and BenQ BL2711U displays at the office. Cheers!

Thank you for this great post!

May I ask how many windows you have open in sum when connected to two external 4k monitors? And you never experience any lag because of the monitors being connected? Can you link me to the specific cable on Amazon that you are speaking of? By "portrait or landscape mode" you are referring to whether the monitor is rotated 90 degrees or not or does that have something to do with something else? Do you think the current 15 rMBP with dGPU would do an even better job handling the two 4k's or would it be the same? Finally, and most importantly, do you run the monitors in the native/best for retina resolution or do you run it at a higher resolution? My hope was to run them in 2560x1440 HiDPi mode. If you have tried higher resolutions, do you notice any performance issues then? If you haven't tried this, would you mind trying it out for me for 15 minutes or so and let me know if you have any problems?


Your post is very encouraging and once you reply, I am ready to pull the trigger. I am sure there are some great deals on 2013 rMBP's and while I wish I could wait a month for the new ones to come out to further drive down the 2013 model, I really need to move on from my current late 2013 13" rMBP piece of **** I have right now (unequivocally, this is the worst laptop I have ever owned).

As an aside, have you tried the Dell UP2715K? Any issues on your late 2013 rMBP?

 

[rdav]

... Why did you recommend the BenQ BL3201PH? I am looking at the Dell P2715Q or P2415Q because of the text crispness that HiDPi offers and it is currently available at an attractive price. Can you be more specific about the struggles you faced when testing a UHD monitor? I don't understand why somebody would want a 34" monitor that isn't HiDPi.

I'm not sure there's such a thing as an "HiDPi monitor". Thou something like the Dell UP2715k would be difficult to use in it's native 5k.

The BenQ BL3201PH is a 32" panel, as it's name suggests. It can be run naked @[3840x2160] or in HiDPi mode via OS-X[10.11]. With SwitchResX offering even more scaling choices. The larger screen can be useful for many applications. Also, the cost can be significantly less than competing Dells outside the USa.

Hi/DPI? This simple site allows you to compare screens quite effectively [ http://dpi.lv ].

 

[campyguy]

Thanks, some interesting info, and from a super-user too. Will have to try those Accell cables. [Reference the B00A7R9I2M /B00A7R9I22 models]? It's certainly odd that the monitor manufacturers would try to cut costs in that area.

Somewhat off topic, but in your mob of Macs, do you happen to have any iMacs running 2x external 4k monitors? Presumably, if those rMBP models can manage it without complaint, then the iMac (2014 & 2015) should have no difficulty. Same with a single external 5k monitor, via MST.

There were 3 events leading to my discovery, one's a bit silly. The first, silly bit was my GF telling me to clean up my desk - I had my rMBP on my large desk with my two displays (on articulating arms) and several peripherals, and I also had some gripes at the time about "lag". I disconnected everything, moved my desk, and reassembled everything - then my array and two TB drives weren't working - but the displays looked pretty good, albeit a bit "slow" in a subjective way. Opening up the Displays Pref Pane I noticed the header in the dialog read "DELL 2715Q" and not the "Dell P2715Q" I'd entered into SwitchResX's prefs for the display. Then, I fired up my second display and then saw that it looked a good as the first display - AND - the first display didn't turn off; this was shortly after Apple issued the 10.10.3 update, which enabled all kinds of goodness in my rMBP including up to 4k on my two Dells @60Hz (that's buried in that massive thread, the day of this bit of Eureka! for my displays. My goof was that I'd accidentally swapped the DP cable ends for the TB cables; Apple TB cables are DP compliant, not "compatible" that most of the cheap manufacturers state in their specs. I now attribute the bit of slowness with the TB cables as they're DP 1.1a compliant - lots less bandwidth per channel than the cables we're using now...

My second bit was I never had a problem at the office with the several Eizo displays - with the PCs hotting up, EDID information showing up in the Control Panel, and what we plotted/printed is what was plotted/printed out. I'm an engineer, specializing in fixing screw ups, so I wanted to figure out what the heck was going on. Swapping the Eizo cables for the cables that shipped with the Dells - all of a sudden, the displays looked better, the PCs didn't hot up, EDID inform... you get the idea. Looking into the reason for SwitchResX's existence in the first place led me to the old Dell EDID hack and the DisplayPort.org web portal which led me to the Pin 20 thing...

I settled on Accell for a few reasons - they were readily available, not too expensive, and they'd been around for a while as a manufacturer and I still can't find a reliable source for Eizo cables. I ordered several brands from Amazon then sat down with them and tested each of them with my trusty multimeter for current conveyance over Pin 20 - only the Eizo, Accell, and Apple/G-Technology TB cables did not convey current over Pin 20. The Accell cables are those that carry DP 1.2 - why use an eye dropper when you can use a large garden hose (my analogy here for throughput... ).

As the iMacs, no, we haven't tested them with 2 4k displays - I'm not going to be back in that office for a few weeks and those desks don't have much more room on them. If I get in touch with someone who's willing to test that out, I'll ask. I don't see why it wouldn't work as the iMacs have far more GPU than my rMBP...

 

[rdav]

... ). As for the iMacs, no, we haven't tested them with 2x 4k displays. I'm not going to be back in that office for a few weeks and those desks don't have much more room on them. If I get in touch with someone who's willing to test that out, I'll ask. I don't see why it wouldn't work as the iMacs have far more GPU than my rMBP...

Thanks. Maybe y'all can post some images too --> on this dormant thread perhaps:
[ https://forums.macrumors.com/threads/share-your-multiple-monitor-imac-setup.1403370/ ]

Also, reference those Accell Cables that you tested. [ http://www.accellcables.com/collect...aav-mini-displayport-to-displayport-1-2-cable ]. It's not clear why they are limited to UHD, and not true 4k. Or why the older (DP 1.1) version [B119B-007J] seems to be priced higher than the current (DP 1.2) editions [eg. B143B-007J]. But well-worth trying anyway! Thanks for the Nfo.

 

[campyguy]

Thank you for this great post!

May I ask how many windows you have open in sum when connected to two external 4k monitors? And you never experience any lag because of the monitors being connected? Can you link me to the specific cable on Amazon that you are speaking of? By "portrait or landscape mode" you are referring to whether the monitor is rotated 90 degrees or not or does that have something to do with something else? Do you think the current 15 rMBP with dGPU would do an even better job handling the two 4k's or would it be the same? Finally, and most importantly, do you run the monitors in the native/best for retina resolution or do you run it at a higher resolution? My hope was to run them in 2560x1440 HiDPi mode. If you have tried higher resolutions, do you notice any performance issues then? If you haven't tried this, would you mind trying it out for me for 15 minutes or so and let me know if you have any problems?

Your post is very encouraging and once you reply, I am ready to pull the trigger. I am sure there are some great deals on 2013 rMBP's and while I wish I could wait a month for the new ones to come out to further drive down the 2013 model, I really need to move on from my current late 2013 13" rMBP piece of **** I have right now (unequivocally, this is the worst laptop I have ever owned).

As an aside, have you tried the Dell UP2715K? Any issues on your late 2013 rMBP?

On my rMBP I often have about 4-10 windows open including 1-2 Finder Windows, unless I'm using CAD or Illy/PS and then I'll keep it to a couple of windows besides the app itself; one of the Finder Windows open with CAD/Illy/PS is the root window of the scratch disk assigned to that app so I can monitor its use.

On the iMacs in my main office I'll see my employees with up to 20 windows open, but all of those iMacs aren't necessarily running at 5k on the main display all of the time and at either 4k or 1440p on the attached display.

We use Spaces and - to me and more importantly - a 3rd-party utility like Spectacle for window management (moving windows between displays and resizing); I also map the Zoom Command to a Control-Z Keyboard Shortcut for quick window size adjustment.

FWIW, we're moving on from Dell's P2715Q displays - BenQ's BL2711U offers more future proofing in its inclusion of HDMI 2, and it's way more OS X-friendly than Dell. My next display at home will likely be this beast: https://pcmonitors.info/reviews/philips-bdm4350uc/ - we demoed one for a while and ordered one, and our clients saw it and have purchased for themselves.

We haven't tried a UP2715K - we use lower-res Eizo displays for our critical work, and they're built like tanks. Any newer displays going in the office are likely going to have a USB-C interface but we're not buying any displays for the rest of this calendar year.

The cables:
http://www.accellcables.com/product...rt-to-displayport-1-2-cable?variant=846829025
https://www.amazon.com/dp/B0163LQUH..._m=ATVPDKIKX0DER&pf_rd_r=7WGT8QYN2NAV83GSBGFA
[doublepost=1470243977][/doublepost]

Thanks. Maybe y'all can post some images too --> on this dormant thread perhaps:
[ https://forums.macrumors.com/threads/share-your-multiple-monitor-imac-setup.1403370/ ]

Also, reference those Accell Cables that you tested. [ http://www.accellcables.com/collect...aav-mini-displayport-to-displayport-1-2-cable ]. It's not clear why they are limited to UHD, and not true 4k. Or why the older (DP 1.1) version [B119B-007J] seems to be priced higher than the current (DP 1.2) editions [eg. B143B-007J]. But well-worth trying anyway! Thanks for the Nfo.

I hadn't thought of posting my layout, as to the office that's off limits for now - we do too much proprietary work. My set ups are standing desks with a 6'x3' table top, with the displays mounted to Herman Miller Dual Flo arms. I use the displays in landscape or portrait mode as needed - portrait for Word/Excel, landscape for CAD work and image editing for work and GB/FCPX for play (I'm the boss until my GF is the boss...).

As to UHD, I can't offer much of an explanation as they're all consumer devices - we may be a production office, but its workspace for civil/structural CAD/modeling/light image editing we're after and not 4k video. With the EDID info being conveyed to my Macs and PCs properly, the displays are feeding back the capabilities of the displays we're using, which is UHD - our couple of "4k" TVs are also reflecting UHD. On one of our displays we pumped a true 4k image to a display and it was cropped at native and looked compressed at full, so we're sticking with what's being fed to us in UHD.

Gotta run to a client's office, I'll check in later. Cheers!