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Guide: Black boot screen + white Apple logo on "unsupported" Macs (boot.efi hack)
- Thread starter Manic Harmonic
- Start date
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Antoni Nygaard
macrumors 6502a
weird i have a iMac 27 late 2009 Quad Core i7 and I have a short board ID like my MacBook 4,1. and the script reports short ID
53kyle
macrumors 65816
According to this:
http://browser.primatelabs.com/geekbench2/2475581
Your iMac does have a short ID and so do 2010 iMacs, so maybe sandy bridge came with the 16 digit board ID? Or thunderbolt?
I'm pretty sure this won't work, but can you try this boot.efi then and follow steps 8 through 11? It just has the next 8 digits replaced by empty space... I know w0lf said this does nothing but I just wanted to see if maybe the fact you had an i7 might make a difference.
w0lf
macrumors 65816
Try my new version of the script.
Download Link : MediaFire
Interestingly enough as of Beta 3 my external monitor started to boot with a black screen with a grey rectangle in the middle and the old grey progress bar and it would also shut down with a black screen.
So going off a hunch I unplugged everything from my Macbook pro and restarted. With that reboot it started booting with the black boot screen. I've plugged everything back in now and it boots with the black screen every time now 😀.
Subsequently I stayed up until like 1AM adjusting my script to work for both 8char and 16char machines (as well as any number in between). Couldn't get sed to insert null characters 😡 so had to read the whole boot.efi as hex convert the board ID to hex pad that with 0s if it was too short and then substitute.
Code:
do_work()
{
echo -e "Now you'll need to enter your password for some sudo commands\n"
sudo -v
echo -e "\n"
echo -e "Unlocking boot.efi"
sudo chflags nouchg /System/Library/CoreServices/boot.efi
cur_time=$(date +%y%m%d%H%M%S)
echo -e "Backing up boot.efi to ~/Desktop/boot${cur_time}.efi"
sudo cp /System/Library/CoreServices/boot.efi ~/Desktop/boot${cur_time}.efi
echo -e "Getting ID hex"
hexedID=$(echo -n $var_ID | xxd -ps | sed 's/[[:xdigit:]]\{2\}/\\x&/g')
hexedID=$(echo "$hexedID" | sed 's/\\x//g')
hexedID=$(echo "$hexedID" | tr 'a-z' 'A-Z')
while [[ ${#hexedID} -lt 40 ]]; do
hexedID=${hexedID}0
done
hexedID=$(echo -e $hexedID | sed 's/..../& /g')
echo -e "Getting boot.efi hex"
xxd -c 26 /System/Library/CoreServices/boot.efi /tmp/___boot.efi
echo -e "Editing boot.efi hex"
sed -i -e "s|4d61 632d 3335 4331 4538 3831 3430 4333 4536 4346|$hexedID|g" /tmp/___boot.efi
perl -pe 'chomp if eof' /tmp/___boot.efi > /tmp/__boot.efi
xxd -r -c 26 /tmp/__boot.efi /tmp/_boot.efi
echo -e "Replacing boot.efi and cleaning up /tmp"
sudo mv /tmp/_boot.efi /System/Library/CoreServices/boot.efi
rm /tmp/___boot.efi-e
rm /tmp/___boot.efi
rm /tmp/__boot.efi
echo -e "Adjusting permissions and locking boot.efi"
sudo chmod 644 /System/Library/CoreServices/boot.efi
sudo chown root:wheel /System/Library/CoreServices/boot.efi
sudo chflags uchg /System/Library/CoreServices/boot.efi
echo -e "Done!\n\nNow all you need to do is reboot twice."
sleep 1
osascript -e 'tell app "loginwindow" to «event aevtrrst»'
}
clear
echo -e "Welcome\n"
var_ID=$(ioreg -p IODeviceTree -r -n / -d 1 | grep board-id)
var_ID=${var_ID##*<\"}
var_ID=${var_ID%%\">}
echo -e "Your ID : $var_ID\nOld ID : Mac-35C1E88140C3E6CF\n"
if [[ ${#var_ID} -lt 21 ]]; then
do_work
fi
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Antoni Nygaard
macrumors 6502a
Are you asking if it affects anything besides just the boot screen? If so, no, to my knowledge it does not.
ACDIT
macrumors member
Actually , i noticed that when shutting down my mac , the usual white screen before the shutdown is now black too !
Yep. Everything is black. Honestly I've been waiting for Apple to do something like this for a long time.
ACDIT
macrumors member
mikecwest
macrumors 65816
I just tried this script....
Was I supposed to modify the script, or is it all automated? I do get a black shutdown screen as I did before the script, but no black start up...
I would love a black startup screen... I am a bit old fashioned as well, I'd like to put the original rainbow apple instead of a white one.
Anyone try this on the public beta 1?
Was I supposed to modify the script, or is it all automated? I do get a black shutdown screen as I did before the script, but no black start up...
I would love a black startup screen... I am a bit old fashioned as well, I'd like to put the original rainbow apple instead of a white one.
Anyone try this on the public beta 1?
w0lf
macrumors 65816
mikecwest
macrumors 65816
yes, restarted twice, did not work... tried again... restarted twice... did not work
set startup disk to another partition, from a clean install of DP1-DP4 update, tried with this, did not work...tried again... restarted twice... did not work
I then set back to original partition and posted here ...
If it matters, i am on early 2011 MBP 15", stock HD, 16GB 1600MHZ
w0lf
macrumors 65816
Well you could try doing it manually.
As for the custom image I would say use BootXChanger but apparently your MPB is the only unsupported device :/
What's the significance of the black screen during boot? By that I mean why would only certain macs have it while other ones don't? I must be missing something.
Weird thing is I installed DP4 on a VMWare install on my Windows machine (I HAD to test it out 😛), and I noticed it was black with the white bar. Made me feel like I was doing a software update on my iPhone!), but then my 2011 MBA is standard grey with black bar.
Weird thing is I installed DP4 on a VMWare install on my Windows machine (I HAD to test it out 😛), and I noticed it was black with the white bar. Made me feel like I was doing a software update on my iPhone!), but then my 2011 MBA is standard grey with black bar.
iVikD
macrumors regular
I'm also on an early 2011 15'' MBP, script doesn't seem to work for me... I'm gonna try a couple more things before giving up on it
mikecwest
macrumors 65816
If you mean, why do I want/need it...The white screen boot lights up the inside of my car. I try not to light up my car in the dark.
If you mean, why do the new macs get it ant I don't? I hardly think that it would be a hardware issue, like the handoff/continuity thing that requires BT LE, which did not come with my mac....
mikecwest
macrumors 65816
Yes, I meant the latter. The handoff thing I get (they haven't and might write drivers for older hardware in the future), but a black boot screen vs grey.. I don't get why some Macs would get it and others don't.
iVikD
macrumors regular
I think it's just one more 'feature' added to new models to encourage older model owners to upgrade, I doubt there's any actual functionality behind it.
It's possible, I'm on DP4 though and it's still working for me. I haven't tried PB1 yet.
----------
Actually, I hadn't booted into mavericks since I did this... I just booted in to mavericks, then back into Yosemite, I can't get the boot screen to be black again. The shutdown screen, is, however black.
To undo the black boot screen
w0lf's script file makes a backup of the old boot.efi file on the desktop. In case you don't like it and want to go back to the old way to boot you can run this in terminal:
sudo chflags nouchg /System/Library/CoreServices/boot.efi
Then copy the backup to /System/Library/CoreServices/boot.efi
Then run these in terminal:
sudo chmod 644 /System/Library/CoreServices/boot.efi
sudo chown root:wheel /System/Library/CoreServices/boot.efi
sudo chflags uchg /System/Library/CoreServices/boot.efi
To get it back again (in case it gets corrupted by other boot.efi's in updates or other partitions)
Back up the NEW boot.efi (i.e., the one that black-boots) from /System/Library/CoreServices/boot.efi before updating or making other bootable partitions (or if it is too late for this, salvage it from a time machine backup assuming you made one).
Repeat the "undo" process but with the new boot.efi instead.
w0lf's script file makes a backup of the old boot.efi file on the desktop. In case you don't like it and want to go back to the old way to boot you can run this in terminal:
sudo chflags nouchg /System/Library/CoreServices/boot.efi
Then copy the backup to /System/Library/CoreServices/boot.efi
Then run these in terminal:
sudo chmod 644 /System/Library/CoreServices/boot.efi
sudo chown root:wheel /System/Library/CoreServices/boot.efi
sudo chflags uchg /System/Library/CoreServices/boot.efi
To get it back again (in case it gets corrupted by other boot.efi's in updates or other partitions)
Back up the NEW boot.efi (i.e., the one that black-boots) from /System/Library/CoreServices/boot.efi before updating or making other bootable partitions (or if it is too late for this, salvage it from a time machine backup assuming you made one).
Repeat the "undo" process but with the new boot.efi instead.
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Okay, so it looks like Apple removed some Board ID's from boot.efi. There's now only 4 Macs in there:
MacBookPro10,1
MacBookPro10,2
MacBookPro11,1
MacPro6,1
After replacing MBP10,1 with my own board Id it's working again.
Not sure why.
@w0lf I was going to change the script so it just changes the MBP10,1 ID instead but I don't know what I'm looking at. Maybe you could make it so that it just finds whatever the first Board ID is, in case Apple changes it again?
MacBookPro10,1
MacBookPro10,2
MacBookPro11,1
MacPro6,1
After replacing MBP10,1 with my own board Id it's working again.
Not sure why.
@w0lf I was going to change the script so it just changes the MBP10,1 ID instead but I don't know what I'm looking at. Maybe you could make it so that it just finds whatever the first Board ID is, in case Apple changes it again?
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