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[Guide] Intel Skylake NUC6 (and Skull Canyon) using Clover UEFI (NUC6i5SYK, NUC6i7KYK, etc)

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I've had re-emergence of the age-old screen blanking / flickering to black problem with upgrade to high sierra. Not sure how I fixed it previously; it can be done though as I had a stable Sierra for a long time.
 
I've had re-emergence of the age-old screen blanking / flickering to black problem with upgrade to high sierra. Not sure how I fixed it previously; it can be done though as I had a stable Sierra for a long time.

Better cables.
 
Not cables. I bought about 5 different ones - all certified. Blanking / flickering is a known problem with intel graphics, even outside the macOS arena
 
Not cables. I bought about 5 different ones - all certified. Blanking / flickering is a known problem with intel graphics, even outside the macOS arena

The key seems to be to use short cables.
My problems definitely went away by using 3' cables instead of 6'.
Cable certification is probably B.S and not helpful in borderline cases/borderline devices.
 
yup, all the cables I got were 3'. I agree the certification thing is prob BS though. But I know the current cable I have used to work perfect on Sierra (after lots of time spent fixing this blanking issue). Once I updated to High Sierra...BOOM, it was back with a vengeance. I notice it seems to be worse if all 4 USB slots are in use, the fan setting in BIOS is too low, with certain programs e.g. VLC or if the render standby option in BIOS is enabled.
 
yup, all the cables I got were 3'. I agree the certification thing is prob BS though. But I know the current cable I have used to work perfect on Sierra (after lots of time spent fixing this blanking issue). Once I updated to High Sierra...BOOM, it was back with a vengeance. I notice it seems to be worse if all 4 USB slots are in use, the fan setting in BIOS is too low, with certain programs e.g. VLC or if the render standby option in BIOS is enabled.

I notice no difference in Sierra vs. High Sierra (my problem is solved with good cables).
 
Thanks for the tip... I may do the same.

I completed my CPU re-paste yesterday with Thermal Grizzly Conductonaut. I also got a rough temperature drop of around 10C: the system idles and runs much cooler according to the Intel Power Gadget. I've tweaked the BIOS fan settings to minimize noise and have screwed the VESA mount to the underside of my wooden desk near the far corner: with that additional noise shielding the NUC is now generally so quiet that the only perceptible sound is a nearby spinning disk array in my NAS.

Any problems with slow boot with APFS?
(trim, which is default with NVMe, is proving to cause slow boot [fsck or equivalent running each boot])

Yes -- it's painfully slow taking several minutes. I rarely reboot and just lock the machine overnight with displays automatically entering power-save mode.

On my verbose boots I see "quickcheck only; filesystem clean" and no logs relating to TRIM. Unfortunately nothing in the system boot log either.

When I boot into recovery, the system blocks for some time on initial SSD disk activity: for example, when performing a `diskutil apfs list`. It might be a similar issue here? It's almost like there's some kind of timeout being reached.

Some earlier HS betas booted much faster with otherwise the same setup as I have now. I do remember seeing a lot of TRIM warnings at one stage, but not on the 10.13 release.

What do you see on your system?

You find any documentation on the dart kernel flag?

The only thing I could find on the DART (Device Address Resolution Table) is discussed in some Apple docs that you may have already seen. As others have also mentioned, the DART allows PCI hardware memory mappings; in the docs above they specifically mention its use on a 64-bit system to map addresses to PCI hardware running in 32-bit address mode and otherwise avoid a bounce buffer copy. I guess the same MMU can be leveraged in virtualization: Docker is using the macOS Hypervisor framework, which may be leveraging the DART?

To confuse the issue a bit more, I just did a clean reboot with `dart=0` and Docker still worked, with

$ sysctl kern.hv_support
kern.hv_support: 1


This wasn't the case when I tried it the first time. I'm now not 100% sure what the best option is. I've since removed the `dart=1` boot arg to let the system do its thing. Docker runs fine on every boot this way. This did not affect the slow boot time further.
 
Some earlier HS betas booted much faster with otherwise the same setup as I have now. I do remember seeing a lot of TRIM warnings at one stage, but not on the 10.13 release.

What do you see on your system?

No problems here, but I'm not using NVMe.
I'm using Samsung SM951/AHCI/PCIex4 with TRIM patch (it seems immune to the TRIM+APFS problems).
The SM951/AHCI is almost as fast as NVMe without the hassle (but hard to find now).
 
RE: Screen flickering / blanking
I seem to have fixed the issue by uninstalling Flux - (an app that changes the colouring of the screen to reduce the blue light later in the day). I think running the fan a bit faster and disabling GPU standby mode in BIOS may help too, as well as correct configuration of RAM - some memory chips are incompatible with NUCs and cause this screen blanking issue as well
 
Hello RehabMan! Thank you for the Guide.
When I patch ACPI (from section "Post Installation"), Terminal responds:
Code:
iMac:nuc.git main$ make
iasl -vw 2095 -vw 2008 -p build/SSDT-NUC5.aml SSDT-NUC5.dsl
Intel ACPI Component Architecture
ASL+ Optimizing Compiler version 20161210-64(RM)
Copyright (c) 2000 - 2016 Intel Corporation
Error 6092 - Could not open file "build/SSDT-NUC5.pre" (Preprocessor Output) - No such file or directory
make: *** [build/SSDT-NUC5.aml] Error 1
What I'm doing wrong?
 
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