# Help me fix my Mac. **URL:** \ **Category:** Factual Questions\ **Created:** [September 7, 2017, 2:22am UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702 "2017-09-07T02:22:06Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [September 7, 2017, 2:22am UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/1 "2017-09-07T02:22:06Z")
I have screwed up my vintage 2012 Mac Pro I won’t tell you how I got here because I hardly remember myself. Something about reassigning the start up disk (I have two 2T discs). When I turn on the Mac it sounds like a vacuum cleaner. Then a light gray screen followed by the message “Your computer restarted because of a problem…” Then the Apple logo and the beginning of a progress rule. Then is a lot of code, beginning with “panic (CPU…” Then it restartThanks. ---
**Author:** ![Weisshund](https://avatars.discourse-cdn.com/v4/letter/w/ba8739/32.png) [@Weisshund](https://boards.straightdope.com/u/Weisshund)\ **Post date:** [September 7, 2017, 2:27am UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/2 "2017-09-07T02:27:01Z")
This any help? [http://www.ninjastik.com/support/how-to-choose-a-startup-disk-on-your-mac/](http://www.ninjastik.com/support/how-to-choose-a-startup-disk-on-your-mac/) ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [September 7, 2017, 2:41am UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/3 "2017-09-07T02:41:29Z")
I have no advice, but I wanted to say that since a rather horrible experience the last time I upgraded the OS, I’ve taken to backing my computer up on a removable 1 TB hard drive every few weeks or so. ---
**Author:** ![nightshadea](https://avatars.discourse-cdn.com/v4/letter/n/7ba0ec/32.png) [@nightshadea](https://boards.straightdope.com/u/nightshadea)\ **Post date:** [September 7, 2017, 2:53am UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/4 "2017-09-07T02:53:29Z")
well other than jokes about macs, dumpsters and fires I got nothing … ---
**Author:** ![AHunter3](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ahunter3/32/368_2.png) [@AHunter3](https://boards.straightdope.com/u/AHunter3)\ **Post date:** [September 7, 2017, 3:43am UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/5 "2017-09-07T03:43:54Z")
Hold down the option key as you boot and see if it lets you pick a different partition to boot from. “But I don’t have a different partition to boot from!”, you may be thinking. But I bet you do. MacOS from approximately 10.7 onwards automatically creates a hidden partition and installs a copy of the base OS along with Disk Tools onto it. ---
**Author:** ![ThisSpaceForRent](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thisspaceforrent/32/345_2.png) [@ThisSpaceForRent](https://boards.straightdope.com/u/ThisSpaceForRent)\ **Post date:** [September 7, 2017, 4:57am UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/6 "2017-09-07T04:57:51Z")
delete your start up disk and reboot. As long as you know your mac ID your device will self identify and load the correct OS. I did it a week ago with splendid results. tsfr ---
**Author:** ![ThisSpaceForRent](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thisspaceforrent/32/345_2.png) [@ThisSpaceForRent](https://boards.straightdope.com/u/ThisSpaceForRent)\ **Post date:** [September 7, 2017, 4:59am UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/7 "2017-09-07T04:59:10Z")
back up first… jeez…always back up!! tsfr ---
**Author:** ![AHunter3](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ahunter3/32/368_2.png) [@AHunter3](https://boards.straightdope.com/u/AHunter3)\ **Post date:** [September 7, 2017, 5:03am UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/8 "2017-09-07T05:03:25Z")
> [@ThisSpaceForRent](#): > > delete your start up disk and reboot. As long as you know your mac ID your device will self identify and load the correct OS. > > I did it a week ago with splendid results. > > tsfr Doesn’t that kind of, like, nuke your files and your settings and your installed 3rd party apps and essentially erase everything you’ve ever done on your computer? ETA: I’ve never done that. Worst I’ve ever had to do was scavenge a hard disk to salvage my files and then reinstall the OS after reformatting the partition. And that was once in 32 years of using Macs. ---
**Author:** ![edwardcoast](https://avatars.discourse-cdn.com/v4/letter/e/cab0a1/32.png) [@edwardcoast](https://boards.straightdope.com/u/edwardcoast)\ **Post date:** [September 7, 2017, 5:10am UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/9 "2017-09-07T05:10:01Z")
> [@panache45](#): > > I have screwed up my vintage 2012 Mac Pro I won’t tell you how I got here because I hardly remember myself. Something about reassigning the start up disk (I have two 2T discs). > > When I turn on the Mac it sounds like a vacuum cleaner. Then a light gray screen followed by the message “Your computer restarted because of a problem…” > > Then the Apple logo and the beginning of a progress rule. > > Then is a lot of code, beginning with “panic (CPU…” > > Then it restartThanks. Telephone AppleCare. Even if your AppleCare has expired on your Mac, Apple will still help you and walk you through what to do. Also, you can bring it to an Apple Store. Your system isn’t that old. I’ve been using the Macintosh for decades and they have never failed me. I can’t say the same for Windows computers and stopped using them many years ago. ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [September 8, 2017, 5:39pm UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/10 "2017-09-08T17:39:54Z")
Holding down the option key worked… exactly once. I had to restart again, and now the option key - or any other key - does nothing. And still the vacuum cleaner sound. Can someone give me the phone # for Apple Care? ---
**Author:** ![iamthewalrus\_3](https://avatars.discourse-cdn.com/v4/letter/i/258eb7/32.png) [@iamthewalrus\_3](https://boards.straightdope.com/u/iamthewalrus_3)\ **Post date:** [September 8, 2017, 5:53pm UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/11 "2017-09-08T17:53:06Z")
Do you have a Mac OS disc you can boot from? Insert the disc and hold down the C key to boot from it. If not, do you have an 8G or larger USB key and another mac you can use to download and create a USB startup disk? If your problem is that your mac is confused about where to start from, then starting from an OS install disk should work. If those don’t work, then the issue is probably something else. Could be some kind of hardware failure. The “vacuum cleaner” sound is the fans spinning up to full when starting, which might just be a normal self-test when things didn’t shut down properly (which they haven’t because it’s not booting correctly). The Mac is like: “huh, something didn’t work last time. Let’s make sure I can crank the fans all the way up in case I failed due to overheating last time.” ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [September 9, 2017, 12:55am UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/12 "2017-09-09T00:55:26Z")
If you get the message about the Mac not shutting down properly it is usually because it detects that the files systems don’t have the clean flag set on them. It will then perform a full file system check. This will take ages. Normally the file system will survive a bad shut down (any modern journalled file system should usually) but sometimes it can’t guarantee things. However what you have sounds a lot like a fault deeper. It may be that the boot block is bad on one disk. It is always important to read the error messages, but most importantly the first message. The default action most computers take with controlled fans is that in the absence of information to the contrary they run the fans flat out, waiting for the temperature sensors to be configured and deliver sensible readings. Not seeing the option key is really odd. That is very deep in the system. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [September 9, 2017, 2:12am UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/13 "2017-09-09T02:12:12Z")
Could the not recognizing the option key be due to using a wireless keyboard? I know I’ve had to dig up the wired keyboard from my closet in years past when it wasn’t responding to wireless keyboard commands upon booting. ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [September 9, 2017, 3:41am UTC](https://boards.straightdope.com/t/help-me-fix-my-mac/795702/14 "2017-09-09T03:41:48Z")
Ugh, never though about a wireless keyboard. Indeed. If it is a narfed SMC, which it very likely is, you will need to reset that. [When and How to Reset Mac SMC (System Management Controller)](http://osxdaily.com/2010/03/24/when-and-how-to-reset-your-mac-system-management-controller-smc/) This is always the next step.