Photoshop Issues with MBP 13" and LG Ultrafine 5K

[Synna]

Dear Community,

I am starting this thread in this subforum, as the issue I am seeing seems to be related to the LG Ultrafine 5K.

Here it goes: My partner (professional photographer) got one of the new MBP 13" when they were released earlier this year with 32GB RAM and I got her a LG Ultrafine 5K for working from home. Unfortunately, connecting the MBP to the display and using software like Photoshop is almost impossible. When she moves Photoshop to the big screen, she can't see her cursor most of the time and the whole experience is unresponsive and laggy in general.

Has anyone ever had this issue and if yes, what is it related to? Is the MBP too weak for the display? Is the display faulty and should be replaced? Is it just Adobe software being not optimized properly? Would an eGPU help? We are really desperate, as the beautiful (and expensive) display is basically just wasted at the moment.

Thank you for your help!

 

[ght56]

Some other members will have more troubleshooting ideas, but two quick questions that immediately come to mind are:

1 - Can you verify that you have the display set to function at 60 Hz refresh rate and not 30 Hz? If the refresh is 30 Hz for some reason, things can be frustratingly laggy.

2 - Can you share a screen shot of what your activity monitor looks like in regard to CPU usage at the time the lag is occurring, sorted by CPU percent?

 

[Synna]

Some other members will have more troubleshooting ideas, but two quick questions that immediately come to mind are:

1 - Can you verify that you have the display set to function at 60 Hz refresh rate and not 30 Hz? If the refresh is 30 Hz for some reason, things can be frustratingly laggy.

2 - Can you share a screen shot of what your activity monitor looks like in regard to CPU usage at the time the lag is occurring, sorted by CPU percent?

Thank you for your suggestions (and sorry for not getting back to you earlier). I'll definitely try to follow the points you mentioned and report back as soon as possible.

Edit: Before posting the results, just a quick update: We tried using a borrowed BlackMagic eGPU and this did not solve the problem.

 

[Synna]

So, first update: It seems the UltraFine 5K isn't even "able" to run below 60Hz, so that can probably be ruled out. I'll take a look at the activitiy monitor, but in the meantime, I have also seen that the UltraFine works fine when you use native Mac programs on it (e.g. notes, ...), so that could be pointing towards the Adobe Suite being the issue.

 

[ght56]

edit-I misread your last post.

Unfortunately I am not extremely experienced with this display and hopefully someone else can add some insight.

 

[Synna]

Okay, so we looked at the Activity Monitor when the problem was occuring and % CPU and % GPU vary, sometimes exceeding 100, but they do not stay that high, so that's probably also not the reason.

I have posted the issue on Reddit too to see if I might gain any insights there.