Grrrr.... EFI update screws up Windows install

Discussion in 'Windows, Linux & Others on the Mac' started by MJL, Oct 27, 2011.

  1. MJL, Oct 27, 2011
    Last edited: Oct 27, 2011

    MJL macrumors 6502a

    Jun 25, 2011
    I tried very hard to like OS X but unfortunately Windows and OS X on a GUID partition are not the best solution for a rapid restore of either one. So with my 2010 Mac mini I resorted to installing Windows on the internal SSD and installed OS X (Snow Leopard and later Lion) on an external HDD.

    Roll forward: Need faster data bus so buy the Mac mini 2011 2.5 with Sandy Bridge last week. Upgrade all OS X stuff and make a backup with Time Machine to external HDD. Slide in USB memory key with Windows install - goes smooth, no problems.

    Make backup using Windows backup/restore and have tested backup & restore a few times (needed to make changes to install so fresh restore - make change - fresh backup). All running well.

    Find out today that there is an EFI update - gr... this does not work from external HDD and needs to be installed from internal HDD with GUID partitioning. Need to do a restore from Time Machine and do succesfully EFI update. Sofar OK, can live with this.

    And now trouble starts - Lion has kindly succesfully hidden the recovery partition and no matter what it cannot be gotten rid off. Boot SL from external HDD: no joy, same with booting Lion from external HDD: no joy. The problem with this is that even if you reformat the internal HDD with "MBR" a windows restore or windows install does not see this as a valid partitioning scheme and does not want to work with the HDD.

    In the end I had to resort to removing the HDD and formatting it on a Windows machine. Half a day lost.

    (by the way: it is possible to remove and get the HDD back in without moving the logic board but it is a fiddly undertaking)

    At one stage SJ said "play nice with your friends", well it is clear that this no longer is the mandate. Apple you've lost me, this was the second and it is the last Apple product I ever buy.
  2. Quad5Ny macrumors 6502a


    Sep 13, 2009
    New York, USA
    If you like Windows so much, how can you not know about diskpart?

    1. Boot off of your Windows install USB stick
    2. Click the Recovery Options button on the first setup Window
    3. Navigate your way through until you find the Command Prompt button
    4. Type: diskpart
    5. Type: list disk
    6. Type: select disk # (where # is the disk you want to erase)
    7. Type: clean (this will erase partition maps/boot records and any OS will basically see it as a factory fresh drive)
      Alternatively you can also use "clean all" to zero the drive (not recommended for SSD's though)


    1. In Disk Utility convert the disk from GPT to MBR (or visa versa)
      Switching back and forth between the two will erase all partition records (and everything else).


    Show hidden partitions in Disk Utility:
    1. Open Terminal
    2. defaults write DUDebugMenuEnabled 1
    3. Launch Disk Utility
    4. Click the Debug menu and choose "Show every partition"

    P.S. You don't have to install EFI updates. If everything works, you can skip them. (EFI updates are like BIOS updates)
  3. MJL thread starter macrumors 6502a

    Jun 25, 2011
    Thanks for the long reply, however....

    I did try diskpart as well (booting from USB key) and it did not clean the whole hard disk - Apple must have done something very, very sneaky. In the end I had to take the HDD out and insert it into the ultrabay HDD caddy on my Thinkpad and use diskpart there (!) to get it working properly.

    I also had found the debug and tried that with booting from both Lion and Snow Leopard (external HDD) but no joy....

    Had hopes that the EFI update would fix the fanspeed on the windows side which always stays at 1800 rpm. Only when it gets to the 90C region the fan speeds up and sounds like a hairdryer. At the moment I am using MacFan0_65 to set the speed to 2300 rpm which keeps everything reasonably good in check.
  4. shortcut3d macrumors 65816

    Aug 24, 2011
    The EFI update appeared to work for me from a OSX 10.7.1 original 500GB Apple Toshiba 5400 RPM connected externally with a Segate GoFlex FireWire 800 cable.

    However on one of two 2011 Mac Mini 2.7 GHz i7 I am getting BSOD after the EFI update. I maintain identical drivers and software on both machines.
  5. MJL thread starter macrumors 6502a

    Jun 25, 2011
    Yeah, I discovered the hard way too that it is not trouble free :mad:. I reverted to the non-AHCI version from misery yesterday. It is my definite impression that no longer does Apple play nice with Windows, SJ's mantra was to play nice with your friends but apparently Apple does no longer regard anyone as a friend. I remember the same attitude from M$N 20 years back before Linux came onto the scene.
  6. shortcut3d macrumors 65816

    Aug 24, 2011
    To confirm, you used the AHCI tweak ( to enable AHCI on your Windows SSD and started having stability problems after the lastest EFI update. Reverting back to basic mode (IDE) your system is now stable? Did you simply change the registry values and replace your MBR with dd? Or did you reinstall Windows all together?

    For my HTPC's there is no reason to run AHCI, except marginally faster boot times. The recording drive is plenty fast to record 3 shows and play back one in IDE mode.
  7. MJL thread starter macrumors 6502a

    Jun 25, 2011
    Since I am purely running windows I use the Windows backup and restore. A long time ago I learned that over time the registry in windows gets fragmented and subsequently issues start to appear. What I do is I do nightly / weekly a backup with FBackup (free utility) to an external drive for my personal data.

    For the OS and installed programs I do a backup with Windows Backup. Then when MSN indicates the monthly patches/updates then I wait until the saturday, backup my personal data and then shove in a bootable USB key (windows install will do) and use the windows restore functionaility to restore a system image.

    In case that there have been issues and / or there has been work done on partitioning as in this case I go into the command prompt (to be found on the USB key) and under diskpart "clear" the internal HDD of everything before doing the restore of the system image. In that way I know for certain that there is no risk.

    However I have used dd to restore the orginal EFI and that worked too - because windows cannot see the AHCI drivers it will boot in the normal mode. Afterwards I reversed the two changes of 3 => back to a 3 again. I have no worries about having to do the latter, it is just that all tied in with some other maintenance work I was doing that I did the complete system image restore. Just ask if you want to know more.
  8. thejadedmonkey macrumors 604


    May 28, 2005
    On a few occasions, I've had to resort to using Windows to clean up a HDD that OS X housed. Not that OS X had any problems with it, mind you. So aggrivating.
  9. shortcut3d macrumors 65816

    Aug 24, 2011
    Wirelessly posted (Mozilla/5.0 (iPhone; CPU iPhone OS 5_0 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9A334 Safari/7534.48.3)

    MJL -- did restoring the MBR back to EFI and having Windows in basic IDE mode fix your stability issues? If so, I'll do that this Saturday. I too am running the Mac Minis on Windows 7 only.

    Stability is key as these are HTPCs so they need to be appliance like to pass the wife test.
  10. jsolares macrumors 6502a

    Aug 8, 2011
    Land of eternal Spring
    have you tried hybrid mbr? i used that to have snow leopard and windows 7 happy on a hackintosh laptop, otherwise 7 wouldn't even install or if pure mbr SL wouldn't
  11. MJL, Nov 4, 2011
    Last edited: Nov 4, 2011

    MJL thread starter macrumors 6502a

    Jun 25, 2011
    Yes it did restore - check your pm.

    PS I have started to use MacFan0_65 to manually set the minimum fan speed and it keeps the machine nice cool - CPU around 7-8% (24/5) and fan at 2200 rpm
  12. MJL thread starter macrumors 6502a

    Jun 25, 2011
    I read the article some time ago and when I came to the remark: "warning hybrid... are flaky!" I abandoned all ideas of running OS X and Windows under different partitioning schemes. I had by that stage tried all kind of methods to restore both a Windows and OSX installation on the same HDD (SSD) and all were cumbersome and took too long.

    In all honesty I cannot remember when I had to do a restore in a hurry (in other words which was not an excercise but the real thing instead) but it is always important to have the plan in place, know that the plan works and have practised the plan so you know you can do it under stress.

    Running both on a MBR partitioned HDD / SSD is possible and actually reasonably easy to implement. By being in this part of the forum you should know how to install Windows without going through OSX' BootCamp partitioning, in other words install Windows as the only OS. What you have to do is the following: With Lion installed you make with Time Machine a backup to external HDD. Install Windows. Install Paragon Partition Manager. If required shrink Windows (if you allocated the whole drive to windows, otherwise not required). Create an Apple HFS partition (remember we are now having a MBR partitioning shceme). Start from Time Machine and reformat in disk utility the Apple HFS partition and then do a restore from Time Machine. (You cannot do a new install - then OS X starts to complain bitterly about no GUID).

    The only problem that I came accross: In Lion you cannot set which partition to boot from, you'll have to use the windows bootcamp facility for that.
  13. MJL thread starter macrumors 6502a

    Jun 25, 2011


    Do not believe that running things natively is always faster. One of my charting programs runs 50% faster under Parallels (Virtual I/O). Also faster under VMware but not as much (about 35%).

    May make for a good backup scenario: Normally run under Windows on dedicated internal HDD but if a hickup occurs boot OS X on external SSD (!) and then run Windows under Parallels. Can make for if a hardware crash happens: running out, grab any other Apple (i)Mac laptop / desktop , plugin external, reboot from external and salvage.

    Motto on speed here is: Always test.
  14. MJL thread starter macrumors 6502a

    Jun 25, 2011
    pinging shortcut3d

    I think the instability is the result of the EFI update - I do not know how to undo that one, may give Apple support a call.

    One disconcerting item that is happening that once every several days I have a loud sound (bang?) like the disk heads being parked forcibly.

    Not happy.....

    Will install an OS X Lion on the remainder of the HDD so that when/if the disk dies I have no issues about only windows being on the HDD when sending it back.

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