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MacBook Pro 15" 2018 Vega 16 (External 1440p 144hz)
- Thread starter Callander
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downside is I need to use the HDMI otherwise my DP cable I’ll need to disconnect and reconnect all the time from my pc to my Mac.
tb3 to hdmi is your best bet honestly... your refresh rate will be stuck at 60 since that's the HDMI 2.0 limit most have... I think HDMI 2.1 is 4k120 (I apologize, I have forgotten)
You can buy somewhat cheap DisplayPort switches that are passive. Good quality cables kept as short as possible are key, though.
I know this is an older thread, but I've had success doing this with the Aorus AD27QD. Used this cable to do it.
The limit is 60Hz at 10-bit 4K with the right active adapter. You can get higher refresh rates by going with a lower resolution. But things start capping out at about 144Hz over HDMI 2.0 if you are doing 2560x1440.
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So, just to be 100% certain, if I have two 1440p displays, one at 144Hz and another at 60Hz, theoretically the MBP 15" 560X card should be able to run both of them?
Sorry if I was redundant with your answer, I just want to be 100% because I do plan on picking up a 27GL850 monitor in the future and I would hate for the MBP not being able to support the 144Hz.
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So, the setup I tried was: Aorus AD27QD + 22" LG 4K UltraFine. I used the Aorus at 144Hz, and the UltraFine only supports 60Hz. It works fine, but it does look rather strange since I could easily tell the difference in refresh rate with the two side-by-side. This was on a 2018 Mac Mini with only the Intel GPU. The 560X should handle it much better than the Intel GPU can.
EDIT: I went UltraWide, so I don't have that setup anymore, but it should be fine. The 27GL850 is the one that I actually wanted, but honestly, the Aorus is a good second choice if you can find it under 500$.
Thanks! That makes me more confident about purchasing it. I'm trying to build a solid dual PC setup. Where I can either have one monitor for the mac and one for the PC and switch to dual Mac/dual PC if needed.
That's awesome! Mind to share your build? I'm debating on getting a KVM so I can stick with one mouse and keyboard for both machines.
My build isn't complete, but I can certainly share some learnings.
The KVM is the part I haven't fully nailed down yet. I really want a KVM that supports DisplayPort 1.4 so I'm not limited to 3440x1440 @ 120Hz, but they aren't yet shipping, with the first I've found due in the next month or so, and it's nearly 400$.
Right now I'm using passive switches, like the one I linked earlier in the thread: A DisplayPort switch, and a USB 3 switch. There is a couple gotchas with these switches:
1) No cables, and you have to add your own hub for the USB switch.
2) I've had some goofiness with Windows and my Topping D30 USB DAC not always "being active" despite the DAC saying it's getting a signal after switching. I usually have to flip the DAC off and on again to resync.
3) The DisplayPort switch is super touchy when it comes to cables, and even which port is used. My PC with a Nvidia 2080 is fine with either port with a good cable. The Mac Mini with an eGPU doesn't like Port 1, but is fine with Port 2. Also only seems to like a couple cables I've tried. Using a Moshi USB-C -> DP cable was rock solid with both the Mini and MBP. I've had my best luck with a 3' CableMatters 8K cable from the switch to my display, and using 6' CableMatters 8K cables to the eGPU and PC. I've had bad luck with the Monoprice DP 1.4 "Select" cables, and they use less insulation.
A lot of YMMV there on the DP switch. I suspect because it is fully passive, it's accepting a lot of noise on the PCB traces, inserting it into the signal the monitor sees (EDIT: Now I'm tempted to open up my switch to see what's in it doing the switching). An active KVM shouldn't have this problem as you get a fresh signal from it's switching chip, but then you are limited to the signals it supports, and it's more expensive.
A good USB-C to HDMI cable like this one from Uni should still work fine for a 1440p 144Hz display with HDMI 2.0 though. I used that with success with the Aorus AD27QD. It's just more annoying to have to go into the display's menu system to switch inputs. The two passive switches I use now is faster, and DisplayPort will have fewer handshake issues in my experience.
A KVM is probably a good idea, but I can't really recommend one at the moment. No experience with them. My main concerns with KVMs are two things:
- Adaptive Sync was added into DisplayPort 1.2a. So it's not clear if a DisplayPort 1.2 KVM supports Adaptive Sync or not, required for FreeSync monitors like the 27GL850. A DisplayPort 1.4 KVM should.
- FreeSync 2 and G-Sync both use proprietary extensions on top of the usual DisplayPort protocol to work. FreeSync uses EDID information for a chunk of it, which should work, and DisplayPort supports moving this data along the wire with the rest of the data no problem. The question mark is if the implementer of the switching chips (Texas Instruments in the better ones) cut corners or not for parts not sitting in the EDID data. I'm mostly worried because I have been burned by folks cutting corners with USB switches.
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So I just pulled a trigger and got a machine with Vega 16 - what cable would you recommend (or brand) for USB c to displayport that will support 2k 144Hz? I've heard and see some that claim to support 4k 60Hz but reviews seem to say it doesn't.
I have a Moshi cable. Amazon no longer lists it, but it is one of the more reliable DisplayPort cables I have.
I have a Uni HDMI cable which is one of the better active HDMI USB-C cables I’ve tried. I haven’t tried their DisplayPort cable but I imagine it should be fine.
It’s mostly that you want a cable that supports the DP alt-mode of TB3/USB-C, instead of having any sort of active converter in it.
you need this cable or similar with dp 1.4 support
www.club-3d.com
Club 3D | USB Type C Cable to DP 1.4 8K60Hz M/M 1.8m/5.9ft
CAC-1557 - The Club 3D CAC-1557 is a DisplayPort™ signal converter. The USB Type C to DisplayPort™ 1.4 Cable is the easiest solution for connecting your USB Type C source device featuring DisplayPort™ Alternate Mode to a DisplayPort™ 1.4 Monitor, Television or Projector and vice versa. Powered...
you need this cable or similar with dp 1.4 support
Club 3D | USB Type C Cable to DP 1.4 8K60Hz M/M 1.8m/5.9ft
CAC-1557 - The Club 3D CAC-1557 is a DisplayPort™ signal converter. The USB Type C to DisplayPort™ 1.4 Cable is the easiest solution for connecting your USB Type C source device featuring DisplayPort™ Alternate Mode to a DisplayPort™ 1.4 Monitor, Television or Projector and vice versa. Powered...
Need is a strong word here. 10-bit 2560x1440 @ 144Hz can be carried over 1.2 (15.9 Gbit vs the 17.28 Gbit limit). Also, the main difference between a passive cable rated for 1.2 and 1.4 is the rating.
My monoprice 1.4 cables are worse than many of my 1.2 cables, for example.
but why buy a cable with is more future proof if the hardware is capable to handle that ?
The monitor isn’t going to pull more than 15.9 Gbit. The 27GL860 supports 1.4 because it uses the same controller as the 35GK950F which does need 1.4 to hit 144Hz.
And Mac laptops are generally constrained to 1.2 anyways.
And again, there’s no material difference between a 1.2 and 1.4 DP cable. I’d rather have a well shielded “1.2” cable than a less shielded “1.4” cable. Especially if you are trying to use a passive switch like the one I linked above.
I’ve got far too many 1.4 cables that looked like they’d work well, but don’t have enough shielding. Right now I use a pair of thick 1.2 cables to drive my monitor (which does need 1.4 to run at 144Hz at 10-bit).
If a 1.4 cable was guaranteed to be at least as shielded as a 1.2 cable, I’d agree. If the cable wasn’t the cheapest thing in the loop at 10-20$ US, I’d probably agree that it’s worth bumping up for “future proofing”. But when you would need to swap out your 2000$+ laptop before the cable needs to be swapped, it’s more that you are probably providing more profit to someone than truly future proofing.
I honestly regret buying the Moshi cable, because it’s overpriced, IMO.