Mac mini 2018 bad UI-performance with LG 5K-Display

[Synchro3]

Here so far everything is smooth. (of course a dedicated eGPU will be even better, but the iGPU works fine in my opinion)

Mac Mini i7, 32 GB RAM

4K Monitor, 3840 x 2160, Looks like 2560 x 1440

 

[Martyimac]

I went to the Apple Store yesterday as well and (same as you) tested a new Mac Mini with Core i5 which was connected to the LG UltraFine 5K display. The Mac Mini had 8GB of RAM. I noticed similar choppy UI-animations (switching 4K YouTube video to full-screen, switching between desktops, etc.). It was disappointing and convinced me that I didn't want to try to run the LG Ultrafine 5K from my Mac Mini which arrives tomorrow. I think it's a little strange since Apple clearly wanted to demo that configuration. They didn't have any LG UltraFine 4K displays around to try.

Once my Mac Mini arrives, I'm going to hook it up to a 27-inch Dell Ultra HD 4k Monitor P2715Q that I own and see how that runs.

I hooked my new mini 2018 with the I5 and 8G of Ram up to my Dell P2715Q and it seemed just fine. Didn't do any heavy lifting with it but internet surfing, email, word processing all up and running and all seemed well. Looking forward to your results.

 

[gusping]

Here so far everything is smooth. (of course a dedicated eGPU will be even better, but the iGPU works fine in my opinion)

Mac Mini i7, 32 GB RAM

4K Monitor, 3840 x 2160, Looks like 2560 x 1440

Thanks. Is it noticeably smoother in native 4K, or 'looks like 1080p' mode?

 

[Synchro3]

Thanks. Is it noticeably smoother in native 4K, or 'looks like 1080p' mode?

A tiny bit smoother in 'looks like 1080p' mode.

 

[ElectronGuru]

I was thinking 16gb too, for 1 4K monitor in 1080p (so no extra GPU power required). Tempted by upgrading to 32gb myself vs paying Apple for 16gb (not much more as i have student discount). I think 32gb is overkill for light use and a 4k monitor though.

Keep the 16 for a few years then upgrade to 64 when needs are higher and prices are lower.

 

[machjava]

I've been reading this thread since picking up a Mac Mini with the i5, 8gb RAM. I had some noticeable lag in the UI on a 4k screen with the Scaled "looks like 2560x1440", since default resolution made everything massive. After receiving my Razer Core X and installing an RX 570 8gb into it, all of that lag is gone. In fact, the whole experience is so much better.

Also, a strange thing I noticed while using only the Mac mini at first. I noticed everything in the UI was sharp and only anything red, like a badge or icon, etc, was blurry around the edges. After installing the eGPU system, those badges and icons are all just as sharp as the rest of the UI. Weird! Anyway, hope this info helps someone

 

[marc_b]

Did anyone who went to the trouble of going to a Store and experience the "choppiness" ask one of the Blue-Shirts (or whatever the color is these days) about it?

I did.
The guy looked genuinely confused and said it's probably the demo version of MacOS doing weird ****, it's used in stores to let customers click random stuff without having to reset everything every day.
He then rebooted the Mini into regular MacOS and suddenly everything was buttery smooth. He proceeded to open a whole bunch of apps including very complex Final Cut Pro and Logic projects and everything was just as snappy as before.

I've had my Mini i5 for about a week and at one point I noticed some stuttering as well but a reboot fixed it. I suppose there are still some minor bugs. In general, it runs flawlessly.

 

[T-Bob]

I got i7/8/512 few days ago and have used it with 8 and 16.

Honestly I could tell very little difference between them, perhaps with 16 the higher 5k scaling was a bit less stuttery but it wasn't that obvious. Similar with comparing it to 550 output on the MBP. Very minimal differences I could see, perhaps the MBP had an edge with the very highest scaling.

It doesn't help testing that using expose can be slow at first, but then the second run it is much faster. There really needs to be a more scientific method to testing like quartz, or some very intense 2D application.

The positive thing to say is that it seems quite usable on 5k at standard scaling, no less so than the 550 which I considered a mostly smooth 60hz experience. Those that notice the slowness are either coming from an environment with a much faster GPU so are used to higher performance (I have never done this except for some brief usage on iMac Pro, which I would not recall well enough to compare) or their systems were becoming memory starved and benefited from the ram upgrade.

 

[Iceberg72]

I just got my first Mac this year, a Mini with an i5 in it. So far, 4k has been an absolute nightmare. I constantly have a problem with it not even starting up the monitor initially. I have found that if I manually set it to sleep mode after I think it's had enough time to be booted, then wait a few seconds it will usually turn the monitor on for me.

But aside from that, the UI lags all the time. I couldn't even use Krita, as the screen lags significantly behind my brush strokes. The mouse was stuttery, causing misclicks and other issues. I was going crazy, even to the point of doing a full wipe and reinstall of Mojave.

Finally out of desperation I started prepping it to sell and recoup some costs. In so doing I hooked it back up to my old 1080p monitor, and low and behold it is smooth as butter now. No lag, no mouse stutter, no krita lag. It's like a new machine.

So from what I can tell, this thing just isn't powerful enough to run 4k without an eGPU.

For reference I have: Mac Mini 2018, Mojave, 16GB RAM, 512GB SSD, Core i5 CPU.

 

[Hessel89]

I just got my first Mac this year, a Mini with an i5 in it. So far, 4k has been an absolute nightmare. I constantly have a problem with it not even starting up the monitor initially. I have found that if I manually set it to sleep mode after I think it's had enough time to be booted, then wait a few seconds it will usually turn the monitor on for me.

But aside from that, the UI lags all the time. I couldn't even use Krita, as the screen lags significantly behind my brush strokes. The mouse was stuttery, causing misclicks and other issues. I was going crazy, even to the point of doing a full wipe and reinstall of Mojave.

Finally out of desperation I started prepping it to sell and recoup some costs. In so doing I hooked it back up to my old 1080p monitor, and low and behold it is smooth as butter now. No lag, no mouse stutter, no krita lag. It's like a new machine.

So from what I can tell, this thing just isn't powerful enough to run 4k without an eGPU.

For reference I have: Mac Mini 2018, Mojave, 16GB RAM, 512GB SSD, Core i5 CPU.

That's definitely not normal. Why don't you return it back to the store?

 

[Iceberg72]

That's definitely not normal. Why don't you return it back to the store?

Bought it online and am past the two week mark so presumed return was out of the equation. So this stuttering mouse and Krita lag aren't normal with a 4k monitor on a brand new Mac Mini. New Hardware + New OS? I figured I would just sit on the monitor for a few months and see if Apple can work out some fixes for these things. Sort of like buying a new model of a car the first year it comes out.

 

[Hessel89]

Bought it online and am past the two week mark so presumed return was out of the equation. So this stuttering mouse and Krita lag aren't normal with a 4k monitor on a brand new Mac Mini. New Hardware + New OS? I figured I would just sit on the monitor for a few months and see if Apple can work out some fixes for these things. Sort of like buying a new model of a car the first year it comes out.

Not sure where you're from but here in the EU a seller must always repair, replace, or refund if goods you bought turn out to be faulty or do not work as advertised. This unit seems faulty so you have every right to claim a refund/replacement.

 

[Stephen.R]

Krita lag

Can someone enlighten me, what's Krita?

What resolution were you running your 4K display at? What applications were running when it was laggy?

The iGPU uses system memory (up to 1.5GB, but it's not reserved - it's dynamically allocated) so if you run low on memory you will see all sorts of performance issues.

Others have confirmed they're able to run at least 2 4K displays (even scaled) with above base memory.

 

[ElectronGuru]

Bought it online and am past the two week mark so presumed return was out of the equation.

Minimally bring it into an Apple store. They can run some tests and give you a cause if not an entire new Mac.

 

[th0masp]

Can someone enlighten me, what's Krita?

Krita is an open source paint program and is GPU accelerated. In my experience the Mac build isn't all that great.

It would be interesting to hear how the Mini fares on a 4k display when running Affinity Photo (there's probably a trial available). That tends to run well on OSX.

 

[head honcho 123]

Just finished setting up my Mac mini with the LG UltraFine 5k. Performs great! No specific noticeable lags or anything like that. I'm just doing general computing so... so far so good!

 

[AbeFroman77]

So what’s the verdict on using a 5k display? I want to get a Mac now, but don’t know if it’s worth waiting to see the new iMac.

 

[head honcho 123]

I've had it for about 1-2 weeks now, and the LG UltraFine 5k works great for me.

 

[Hessel89]

I've had it for about 1-2 weeks now, and the LG UltraFine 5k works great for me.

I’m on the brinck of buying the exact same setup. Do you also use the Magic Mouse / Magix Trackpad? If so, how is the bluetooth performance?

 

[Ploki]

This makes no sense.
When i use 1920x1200 @2x scaled on 2012 mbp on iGPU 4000hd its fine.

When i used my returned i9 on the same res on the same 630 HD it worked FINE.

So this is 3840x2400 that’s fine vs 4K 4096x 2304 that’s NOT FINE?

So ~24k pixels makes it stutter... How?

Talking about the 4K that supposedly also stutters

 

[Stephen.R]

This makes no sense.

Keep in mind that MBPs with a dGPU never use the iGPU for the external display - it forces the use of the discrete chip.

 

[Ploki]

Keep in mind that MBPs with a dGPU never use the iGPU for the external display - it forces the use of the discrete chip.

Yeh i know - thats why I explicitly stated running the internal screen at maximum scaled resolution. (I have istat menus that tell me when dGPU is used)

 

[Spectrum]

This makes no sense.
When i use 1920x1200 @2x scaled on 2012 mbp on iGPU 4000hd its fine.

When i used my returned i9 on the same res on the same 630 HD it worked FINE.

So this is 3840x2400 that’s fine vs 4K 4096x 2304 that’s NOT FINE?

So ~24k pixels makes it stutter... How?

Talking about the 4K that supposedly also stutters

Under which situation are you using (@2x)4096x2304? On the mini and when connected to a 4K display?
If so, maybe the difference is due to the final scaling. The MBPro final display is only 2880x1800, compared to 3840x2160.

 

[Ploki]

Under which situation are you using (@2x)4096x2304? On the mini and when connected to a 4K display?
If so, maybe the difference is due to the final scaling. The MBPro final display is only 2880x1800, compared to 3840x2160.

Ultrafine 4k is 4096x2304.
Mbpro is 2880x1800 but the rendered desktop is still at 3840x2400 for “more space”, scaled to 2880x1800.

On ultrafine 4k is rendered at 4096x2304 and not scaled.

I have nothing yet, havent recieved my mini yet and cant find stock in EU for the ultrafine 4k

 

[Spectrum]

Ultrafine 4k is 4096x2304.
Mbpro is 2880x1800 but the rendered desktop is still at 3840x2400 for “more space”, scaled to 2880x1800.

On ultrafine 4k is rendered at 4096x2304 and not scaled.

I have nothing yet, havent recieved my mini yet and cant find stock in EU for the ultrafine 4k

I don't think anyone is saying that driving a 4K ultra fine at native 4096x2304 or at 2048x1152(@2x) is a problem for the UHD630.
The potential issues arise when trying to:
1. Drive a 5K display (should still be mostly OK I would think).
2. Using scaled resolutions that require rendering off screen at much higher than 4K or 5K.
3. Driving more than one 4K or 5K screen (especially with scaling).