As soon as the M1 Mac mini arrived, I tore it down to confirm a few things Apple didn’t make clear. All M1 Macs come with Thunderbolt 4 ports. I prepared my Mac mini test station with three monitors: Samsung 34-in Thunderbolt 3 ultrawide QHD, LG 27-in DisplayPort UHD, and ASUS 15-in portable USB-C FHD. This setup has been working great through RX Vega 56 Nano Gaming Box with my 2018 i5 Mac mini. The Apple integrated graphics card cannot run more than two displays at once.
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Taking this Late 2020 M1 Mac mini apart is very similar to the 2018 model. Flip it upside down then pry the black plastic base cover would expose six TR6 screws. The are three antennas with separate cables going to the logic board headers, one of the antennas is mounted on the bottom metal shield. The antenna connector is secured in place with a T6 screw.
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Another set of four T6 screws mount the cooling fan on top logic board. Apple could have redesigned the M1 Mac mini to be much smaller. The logic board is barely twice the size an iPhone 12 mini.
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Unlike the cooling system in the Intel unit, the heatsink in this M1 Mac mini is a beefy block. In my opinion, thermal dissipation with this new system is better. On the backside of the logic board is a pair of Texas Instruments USB-C controllers [CD3218B12].
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I was most interested in identifying the Thunderbolt controller/s. It’s a nice surprise to see two Intel JHL8040R controllers providing dedicated connection to two Thunderbolt 4 ports. Last but not least is the power supply. Apple uses the same internal 150W (12V~12.5A) PSU as found in the 2018 Intel Mac mini.
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At the moment Thunderbolt devices are working well with Apple M1 Macs. Due to no ARM drivers, Radeon graphics cards do not work and therefore eGPU is a no-go.
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Precisely. Seems like I was on the mark about AMD drivers not being compiled for ARM being the main reason why eGPU is not functional. Saturn Pro with Vega 64 connected to the M1 mini:
Also looks like your photography skills are on-point. Lovely teardown!
@mac_editor, Thank you for the confirmation. I’m upgrading to Dev Beta 11.1 that came out this afternoon. We have to keep our hope up that drivers will arrive eventually. 🙂
Hey @itsage, thanks for the teardown, was itching to see it actually. Does it look like M1 SoC is just sitting on a hotglue? is there a chance it’s actually socketed with some sort of micropins or I’m overthinking it? Also, those ram chips thermal compound dots look like they wouldn’t mind to have some thermal pads added (as in MBA2020/Intel cooling mods) for better conductivity, right? Now I’m super curious to see what’s inside M1 MBA, seems like that odd heatsink in 2020 MBA/Intel was actually designed for m1 and just used for Intel’s last gen for… Read more »
@zvz, I don’t think hot glue was all Apple uses to secure the M1. It looks too low to have a socket underneath. We could apply thermal pads on all the chips under the heatsink. I will open up the M1 MacBook Air soon to take a look.
Well it’s also secured by the heatsink anyway, I’m just wondering why else would they use glue around the corners of the chip, I guess we’ll just wait till someone tries to pry it open and see what happens 🙂
Awesome, looking forward to seeing it.
Cheers!
@itsage, any idea if a Thunderbolt hub with multiple graphic outputs can run multiple displays thus passing the two display limit? For example, two displays off a OWC Thunderbolt hub with dual HDMI off a single TB3 port and one off the Mac mini built-in HDMI? Of course, the integrated GPU would have to do all the work, but that might give a clue about future eGPU potential…
https://eshop.macsales.com/shop/docks/owc-thunderbolt-3-mini-dock
@mar_kelp, I don’t know if that’s possible. I tried a Thunderbolt 3 to dual DP adapter and only one DP monitor came on. It seems the second display connection is hardwired to the HDMI port. I could only get either the ASUS USB-C FHD monitor working or the TBT-dualDP adapter connected monitor at a time.
@itsage could you please run an ssd speed test, if there are any working on arm?
@zvz, My unit has 256GB and it’s not very fast. I tested with AJA System Test and R/W was right around 2,200 MB/s. @mac_editor which drive capacity does your M1 Mac mini have and what’s the speed?
@itsage, oof, I imagined it’d be faster, bc PCIe 4.0 and apple’s “twice as fast ssd* *conditions apply” lingo, but hey, that’s a data point we have now, thanks.
That’s for Air. Mac mini and 13” Pro had already super fast SSD. Anyway it should faster than previous generations, I’ve seen some test/video: MBP 16” can reach 3200MB/s
Posted by: @itsage I was most interested in identifying the Thunderbolt controller/s. It’s a nice surprise to see two Intel JHL8040R controllers providing dedicated connection to two Thunderbolt 4 ports. Last but not least is the power supply. Apple uses the same internal 150W (12V~12.5A) PSU as found in the 2018 Intel Mac mini. According to its data sheet, this TB controller supports Displayport 1.4. Hopefully that means I could drive my DIY 5K monitor with a single DP cable, as I do today from my eGPU. As long as I can find a TB-DP adapter that supports DP 1.4?… Read more »
Is there any way to check the clock speeds of CPU and GPU cores? I’d love to know more about the clock behaviour of this chip. Since it’s under active cooling it would be interesting to see throttling behaviour. If any.
@Leovinus,
:p yes there is. Stay tuned for updates.
@Eightarmedpet, If I didn’t have the 2018 i5 Mac mini, I’d buy the Intel version over M1 one. This is the first generation of a brand new architecture. While you see the performance benchmarks praising the new chip, I think it’s skewed. Taking this unit apart was clear evidence the current design is a convenient shell that didn’t require new tooling. The next Apple Silicon Mac mini with a redesign is the one to buy. @mac_editor, Please feel free to make updates to the OP with your findings. I got a couple hours after work yesterday to do teardown and… Read more »
@itsage, I am writing up a separate post as there’s lot of info to cover. Your teardown looks neat as it is so I wouldn’t want to change its scope.
@itsage, Where’d you find your wallpapers by the way? They’re beautiful.
@Leovinus, They’re stock wallpapers in macOS Big Sur. They remind me of driving through Pacific Coastal Highway. Beautiful scenery through there!
@itsage, people are saying it can do 5K on an LG UltraFine 5K display but I don’t believe it because you can only connect one display to a Thunderbolt port of an M1 Mac. Is it possible it can do 5K with dual link SST but not do two separate displays? Do you have a Thunderbolt to Dual DisplayPort adapter and a dual cable 5K display to test? The usual methods of checking the output resolution (AGDCDiagnose and SwitchResX) do not work on the M1 Mac. Is there a “log show” predicate that can show the info? #2,043 Forum… Read more »
@joevt, I don’t think M1 Macs are able to power the 1st gen LG 5K UltraFine at full resolution. I tested with a Thunderbolt 3 to dual DisplayPort adapter to two DP monitors and only one would work. I will test with the HP Z27q (a dual DP monitor) next. My guess is it will work at [email protected] only.
@itsage, Why would the second gen LG UltraFine 5K be any different? As far as I know, neither gen has a single DisplayPort connection 5K mode, even if you lower the refresh rate to 30 Hz.
@joevt, Right, the only difference is the USB-C host compatible Titan Ridge controller in the 2nd generation.
Great tear down as ever! And yeah, great photos and in such a short time frame! It looks to me like a next gen Mini could be half the size if they redesigned the cooling (this looks like a bit of a retro fit using existing tooling).
Now you have this mini to play with, how do you feel the day to day performance compares to the intel Minis and would buying an Intel mini now be a crazy idea?
Hey! don’t give them any ideas @Eightarmedpet. I mean, they could make a super tiny Mac mini that has the size of a disk-drive, sure, but if they keep it “big” they might shove twice the CPU and GPU cores into it and have a mini Pro! 😉
@Leovinus, thats good point! Totally didn’t see it from that perspective, there will be more powerful Mac minis so maybe they are keeping it that size to accommodate…
@Eightarmedpet, honestly I was mostly joking. But I’d love to see a mini Pro. I’m sure there will be a redesign soon-ish to mark the break between Intel and ARM visually for consumers. A… and a Pro machine would certainly benefit from an eGPU option hehe With the current size they could seriously beef up the capabilities within the thermal envelope it has. The PSU is way overpowered for what the M1 mini pulls too (meaning less efficiency since you’re way off the sweet spot) since I understand it’s the same as before. And I love the design as is… Read more »
Posted by: @itsage All M1 Macs come with Thunderbolt 4 ports. Apple can’t call it Thunderbolt 4 because Thunderbolt 4 requires that a Thunderbolt 4 port can do dual 4K displays. The M1 Macs cannot do dual 4K displays because the Thunderbolt controller has only one DisplayPort connection. Posted by: @itsage It’s a nice surprise to see two Intel JHL8040R controllers providing dedicated connection to two Thunderbolt 4 ports. The Thunderbolt controller is built into the M1. The JHL8040R is just a retimer. I guess a retimer helps to get the signals from the M1 to the ports. I suppose… Read more »
Great info!
What performance do those three ports offer? Since the TB4 hub is fed with a single TB stream from the host at 40Gbps, the performance could be significantly lower if all ports are in use?
Luxmark reports the speed of the M1’s GPU as 1000Mhz. I tested the M1 with 8GB memory. Photoshop (Intel) performance is working well with very large TIFF photos. I didn’t notice any lag there and I am a very fussy b’stard. Lightroom and Premiere should work fine because they both use low res proxies in the viewport by default. I next did an After Effects stress test using raw videos shot in S-Log with a Lut applied to the large comp. There are 66 layers in this comp, that would be too much for any machine with less than 32GB… Read more »
One thing interesting about the M1 Macs is that the ioreg shows two Thunderbolt controllers that each have two AppleThunderboltDPInAdapter which means you could connect four displays total, two displays per port (if the GPU had four DisplayPort outputs).
The ioreg also shows a new adapter type AppleThunderboltUSBDownAdapter which is for USB4 tunnelling of USB 3.2.
@joevt, You could be onto something here. Magically using the TB3 to Dual DP adapter with a dual DP 5K monitor like LG UltraFine and HP Z27q works in full resolution. I tested this same adapter with two separate single DP monitors before and only one monitor came on. When I tried a TB3 cable to Samsung 34-in monitor and a USB-C to DP cable to LG 4K monitor, only one monitor came on.
@itsage, to be sure, does the HP Z27q have an onscreen menu that shows 5120×2880 resolution? My Dell UP2715K shows the input resolution in its onscreen menu.
What is the behaviour when only the first DisplayPort of the HP Z27q is connected? Is the result 4K? Can you notice a difference between real 5K and fake 5K (which is 5K framebuffer scaled to 4K output by the GPU then scaled up to 5K by the display)?
Can you dump ioreg -filw0 with real 5K (two DisplayPort) and again with fake 5K (one DisplayPort)?
@joevt, Yes the monitor info box shows [5120 x 2880 60Hz]. I was posting the ioreg -filw0 dump but the output must have had too many characters so the post was not able to load. My HP Z27q monitor is not in the best shape. It actually works more consistently with dual DP than single DP. It has a hard time detecting input signal when there’s only one DP cable connected.
@itsage, yes, ioreg output is huge, so zipping it is usually a requirement. Thanks for the picture of the onscreen menu – it definitely proves that it is using 5120×2880 input.
@joevt, Can you expound on how Apple made this work?
@itsage, I am guessing the Thunderbolt controller does have two DisplayPort connections to the GPU like any Mac Thunderbolt controller does. The M1 Mac will use them for one display only – either a tiled display like the LG UltraFine 5K or HP Z27q or Dell UP2715K or a non-tiled single display like a 4K display or a 6K display with DSC. It seems that while the M1 can produce two DisplayPort outputs from Thunderbolt, it cannot treat them as a separate display. It’s like with the Nvidia Titan X (Maxwell) card I have – you can connect 4 displays,… Read more »
Posted by: @itsage @joevt, You could be onto something here. Magically using the TB3 to Dual DP adapter with a dual DP 5K monitor like LG UltraFine and HP Z27q works in full resolution. I tested this same adapter with two separate single DP monitors before and only one monitor came on. When I tried a TB3 cable to Samsung 34-in monitor and a USB-C to DP cable to LG 4K monitor, only one monitor came on. Hi there! What TB3 to dual dp adapter are you using? I am using the mono price one which works on old… Read more »
@Weslay Xu, It’s a CHOETECH TB3 to dual DP adapter but I think many brands share the same manufacturer.
Intel TB and TI usb chips? Wait, didn’t they say that the tb and usb io was integrated into the M1 during their keynote?
When connecting the M1 Mini to the XDR 6K 60Hz display, would the usb-c hub
– run at usb 2.0 speed like on non-Navi macs
– run at usb 3.0 speed like on Navi macs
are we 100% sure M1 macs have DP 1.4 with DSC?
A modern DSC-based 4K 144Hz monitor like the LG 27GN950 would work without resorting to chroma subsampling, right?
This is proof that it works in the first place (posted on reddit from a guy with an M1 mac):
@High Sir, I’m pretty sure it’s DSC
#31
Need someone to test the USB port for 400 MB/s file I/O to be sure it’s getting 5 Gbps.
Not 100% clear about HBR3 or HBR3 + DSC yet. Need someone to test 8 bpc modes that require that bandwidth (I say 8 bpc because 10bpc modes could transmit as 8bpc to meet the bandwidth restriction – macOS doesn’t use 6bpc modes).
For 1920×1080, you need to go higher than 240 Hz to get beyond HBR2 for 10bpc. HBR3 can do something like 360 Hz for 8 bpc.
Interestingly enough there’s some kind of bug on Big Sur with non M1 Macs regarding DSC…it seems that it’s not working at all anymore. Not sure if it’s related, just thought I would mention it! Monitors that use DSC to achieve high refresh rates without chroma subsampling are rate limited on Big Sur, it’s affecting all brands too (ASUS, Lg, etc).
So all that is missing to use an eGPU are drivers?
I am able to play non AAA games just fine on the MacBook Pro M1. But it cannot even remotely handle my 38″ monitor. Would be in heaven if I could connect an eGPU.
@Joey Roman,
Yep, Mac OS (Radeon) GPU drivers for ARM M1 models are the missing link.
Won’t happen until they have an M1 Mac with a Radeon GPU, if ever, but fingers crossed they support people who have an eGPU.
There might be some difficulty making a discrete or external GPU work with the unified memory architecture because they have to make sure the video signals, decoding, 3D models and textures are sent to the video card’s memory without causing conflicts with the taks UMA does.
I have it connected to a 49 inch 4K display and the interface speed is better than the 5700 XT, especially video playback. Rendering in Media Encoder is another story, but not too bad.
Posted by: @craftsman Posted by: @Joey Roman So all that is missing to use an eGPU are drivers? I am able to play non AAA games just fine on the MacBook Pro M1. But it cannot even remotely handle my 38″ monitor. Would be in heaven if I could connect an eGPU. I have it connected to a 49 inch 4K display and the interface speed is better than the 5700 XT, especially video playback. Rendering in Media Encoder is another story, but not too bad. Oh, I just meant gaming on my 38” is a no go lol.… Read more »
Posted by: @Joey Roman Posted by: @craftsman Posted by: @Joey Roman So all that is missing to use an eGPU are drivers? I am able to play non AAA games just fine on the MacBook Pro M1. But it cannot even remotely handle my 38″ monitor. Would be in heaven if I could connect an eGPU. I have it connected to a 49 inch 4K display and the interface speed is better than the 5700 XT, especially video playback. Rendering in Media Encoder is another story, but not too bad. Oh, I just meant gaming on my 38” is… Read more »
Posted by: @ikir Posted by: @Joey Roman Posted by: @craftsman Posted by: @Joey Roman So all that is missing to use an eGPU are drivers? I am able to play non AAA games just fine on the MacBook Pro M1. But it cannot even remotely handle my 38″ monitor. Would be in heaven if I could connect an eGPU. I have it connected to a 49 inch 4K display and the interface speed is better than the 5700 XT, especially video playback. Rendering in Media Encoder is another story, but not too bad. Oh, I just meant gaming on… Read more »
@craftsman
Yes I mean mobile / Mac mini. We all are comparing notebooks and low-end Macs and Apple Silicon is already impressive, GPU performance too. But you can’t expect to play in 4K with first generation, low-end solutions especially when most games are incredibly demanding on 4K resolution even with high-end GPUs like 5700 XT.
it is an impressive start… we will see if eGPU support is coming and which performance will M1X bring!
Hi,
I have Mac mini 2018 8th i7 64GB, I want buy a Blackmagic magic EGPU and also i’m working with FCX and Davinci resolve. Is it good or not?