M3 Max - MacBook Pro - Display Lag

[senohpoxas88]

I just got the new MacBook Pro - M3 Max w/ 64GB RAM. I'm upgrading from an M1 Max.

I have two displays, a Pro Display XDR, and the LG Ultrafine 5K. I used them on my M1 for years, and never had an issue. But with the M3, it's horrible. It seems like it cannot handle powering these two screens. Often, the monitors will stutter, showing lagging video, and the LG display seems to turn off for a few seconds every 15min or so. This happens after a fresh reboot when I'm not doing anything more than web browsing, so I doubt I'm out of resources.

Using just the XDR seems fine, but I really don't want to go down to two monitors. I did restore from a backup on my machine. Is it possible it's software? Is there anything I could check before wiping the machine?

Any thoughts would be really appreciated

 

[Bigwaff]

Have you tried different TB port combinations to see if the issue resolves in a certain config?

 

[senohpoxas88]

just tried, same result. Even with them flipped, it's still the same monitor that turns off randomly. No issues when plugging it back into my M1

 

[Malus120]

I hate to be that guy but... Is it possible your Mac is still (Spotlight) indexing?
Two things you could try if that's not it that don't involve wiping the machine:
1. Restart in Safe Mode and see if the issue still occurs.
2. Install (a fresh copy of) macOS to an external, boot from that and see if you still have issues.
3. Try different cables if possible
I'm sure there's a lot else but that's all that comes to mind right now. If the problem persists, return it. The M3 Max MBP should have no problem driving 2 displays (even if they are 5K and 6K)

 

[flybass]

I hate to be that guy but... Is it possible your Mac is still (Spotlight) indexing?
Two things you could try if that's not it that don't involve wiping the machine:
1. Restart in Safe Mode and see if the issue still occurs.
2. Install (a fresh copy of) macOS to an external, boot from that and see if you still have issues.
3. Try different cables if possible
I'm sure there's a lot else but that's all that comes to mind right now. If the problem persists, return it. The M3 Max MBP should have no problem driving 2 displays (even if they are 5K and 6K)

why would indexing (clearly a cpu op) even interfere with the gpu? It sounds like you should exchange the machine if still in the return window.

 

[citivolus]

Are you running the same version of macOS on both machines?

 

[senohpoxas88]

Tried Safe Mode, still there. Same version of macOS.

I'm starting to think it's a compatibility issue with my LG monitor. It feels like this monitor disconnects, which causes the other monitors to slow and reset, and then it reconnects.

I found a firmware update for the LG, but I've tried to install it with both machines and it fails. (Even with only one monitor connected in safe mode).

This seems so odd to me though, as I've used this display for years without any issues on my M1

 

[TheRealAlex]

Tried Safe Mode, still there. Same version of macOS.

I'm starting to think it's a compatibility issue with my LG monitor. It feels like this monitor disconnects, which causes the other monitors to slow and reset, and then it reconnects.

I found a firmware update for the LG, but I've tried to install it with both machines and it fails. (Even with only one monitor connected in safe mode).

This seems so odd to me though, as I've used this display for years without any issues on my M1

Same thing happened to me. You have to Limit in Settings your MacBook Pro to 120hz it’s probably as in my case trying to push 144hz.

 

[rorydaredking]

Tried Safe Mode, still there. Same version of macOS.

I'm starting to think it's a compatibility issue with my LG monitor. It feels like this monitor disconnects, which causes the other monitors to slow and reset, and then it reconnects.

I found a firmware update for the LG, but I've tried to install it with both machines and it fails. (Even with only one monitor connected in safe mode).

This seems so odd to me though, as I've used this display for years without any issues on my M1

Clearly they have done something (undocumented) with displays with M3.

15+ years difference in display tech but same broad principles for me and someone else - Working perfectly on old M2 Max Mac and same displays not working on M3 Max.

https://forums.macrumors.com/threads/external-display-split-into-3-sections-on-new-m3-max-mbp.2411583/?post=32750682#post-32750682

 

[senohpoxas88]

Same thing happened to me. You have to Limit in Settings your MacBook Pro to 120hz it’s probably as in my case trying to push 144hz.

hmm, the monitor that acts up does not have an option for changing the refresh rate. The 6k is at 60hz