Can I reinstall the operating system (Mountain Lion) that came with my iMac

[Peter Finkill]

Hi

I have a 27inch iMac that I bought in 2009.

iMac (27-inch, Late 3009)
Processor: 3.06GHz Intel Core 2 Duo
Memory: 12GB 1067MHz DDR3 (Originally 4MB)
Graphics: ATI Radeon HD4670 256MB
Hard Drives: 1TB internal + 1TB external for backups​

It came with Mac OS 10.6.2 (Snow Leopard) and when I first got it, it was very fast at doing all tasks.
However over the years with the upgrades of the operating system it has slowed down enourmously and is sometimes painful to use with constant rainbow wheel and often having to force quit some applications. I am currently running MacOS Sierra v10.12.3.

Is it possible to rebuild the iMac and go back to how it was in 2009? I only use the basic software that came with the iMac when I got it so there is no special software applications to update. I run a full backup with an external 1Gb disk doing backup of the internal iMac 1 Tb hard disk. I assume that means I would be able to reinstall my documents and photos ok?

Is this possible to do and how difficult would it be (and any problems it would create?). Or is there another way to speed up this iMac?

Thanks

Peter

 

[oldscribe]

Hi,

Is it possible to rebuild the iMac and go back to how it was in 2009?

As you have the disks then yes.

Is this possible to do and how difficult would it be (and any problems it would create?).

Not difficult at all but some of the latest software may not run on the old OS X.

Or is there another way to speed up this iMac?

More ram, I upgraded my 2010 MacBook to 8GB with greta speed results. Also software like Dr Cleaner I think helps, have a look here.

https://www.macupdate.com/app/mac/52661/dr-cleaner

 

[Peter Finkill]

Thanks. I have already upgraded the RAM to 12Gb but that doesn't seem to have made much difference.
Is there a guide to show how to rebuild the iMac with the original MacOS disk?

 

[oldscribe]

Hi,

First do a full back up then the following.

1)Insert the Snow Leopard DVD
2)Restart your computer.
3)While your computer is restarting, hold down the alt/option key. It will then ask you which drive you want to boot from. Select your DVD drive.
4)From there you can select Disk Utlity from the Utilities menu and format the drive, or choose the "erase and install" option.

 

[Peter Finkill]

Great thanks.
Seems straightforward enough.
I'll give it a try.
Can I then stop the automatic updates of the OS?

 

[oldscribe]

Hi,

There are many ways of achieving that , one way would be to turn off background updates in App Store preferences. You can create a profile or use a terminal command if comfortable with terminal, think it would be something like this.

sudo defaults write /Library/Preferences/com.apple.SoftwareUpdate AutomaticDownload -boolean FALSE

 

[Peter Finkill]

One last thing.
I am a bit nervous about my photos in iPhoto.
I'm pretty sure that I have them backed up using Time Machine on my backup drive but I'm still nervous.
Is there any way to check that these are backed up ok or manually saving all of my photos in iPhoto?

 

[oldscribe]

Hello,

Is there any way to check that these are backed up ok or manually saving all of my photos in iPhoto?

Possibly move your photos to another area on your hard drive.
Go to the original location and enter time machine restore to see if they are there.

Personally I always create a backup of my photos on 2 other external HDD's just to be safe, as I take my photographic memories very seriously. Don't just rely on Time Machine.

 

[Peter Finkill]

Thanks.
Where are the photos in iPhoto kept on the hard drive?
How do I identify them?

 

[oldscribe]

Hi,

By default, Photos creates its library in your Pictures folder, you should be able to just drag it to the desktop.

 

[Spawn_Dooley]

Yes, follow oldscribe's instructions, & as you say you are a little nervous, this is healthy. Drag anything (personal files: photos, docs etc) you cannot live without onto a thumbdrive or ext HD.

 

[Peter Finkill]

Thanks.
Sorry but I cannot find a Pictures folder.
Is it under Documents, Applications or Desktop coz I cannot see it under either of those?
Is each photo saved individually with a file extension? What extension?
Seperate folder(s)?

 

[Spawn_Dooley]

Open a Finder window & select your Mac in the left pane. It will be listed under "Devices".
Select your Hard Drive (MacintoshHD).
Select Users.
Select your User Name.
Look for the Pictures folder.

 

[Peter Finkill]

Found it. Thanks for your help