Trying to rid my used iMac of Windows 7

[Melissa Runnels]

Howdy, all.

I've just been given an iMac that is running Windows 7 Pro OS. I want to remove it & replace it with Mavericks or the newest MacOS that is compatible. I've tried restarting +Option key, & the only start-up disk I get is Windows. I've tried looking for the hard disk partitions, but I'm still not seeing a MacOS of any stripe.

Is iit possible to completely wipe the original OS from an iMac? Or just to hide it?
Really can't stand Windows & its infinite updates. I think it's also eating a huge amount of RAM....

 

[nrubenstein]

Howdy, all.

I've just been given an iMac that is running Windows 7 Pro OS. I want to remove it & replace it with Mavericks or the newest MacOS that is compatible. I've tried restarting +Option key, & the only start-up disk I get is Windows. I've tried looking for the hard disk partitions, but I'm still not seeing a MacOS of any stripe.

Is iit possible to completely wipe the original OS from an iMac? Or just to hide it?
Really can't stand Windows & its infinite updates. I think it's also eating a huge amount of RAM....

Do you have access to another Mac? You can put the installer on a USB key.

 

[Melissa Runnels]

I can make that happen. Will the computer automatically configure things as separate disks/partitions?

Thanks,
Melissa

 

[RUGERMAN]

I can make that happen. Will the computer automatically configure things as separate disks/partitions?

Thanks,
Melissa

Start up with an external disk or cd then erase the internal drive and then install.

 

[Melissa Runnels]

If the MacOS is downloadable, I should be able to download to the external & then install from there, rather than using a disk -- true?

 

[nrubenstein]

If the MacOS is downloadable, I should be able to download to the external & then install from there, rather than using a disk -- true?

Get on another Mac, download Yosemite, and use Lion Diskmaker to create a bootable USB key. (You need an 8GB key.) Lion Diskmaker will take a while, but do everything automatically.

Then, you can option boot into the drive selector. FWIW, I've found that it can sometimes take a while for the other boot devices to show up in the menu. Give it a minute, and you may even need to unplug and replug the key in.

----------

If the MacOS is downloadable, I should be able to download to the external & then install from there, rather than using a disk -- true?

Yep.

 

[bradl]

I can make that happen. Will the computer automatically configure things as separate disks/partitions?

Thanks,
Melissa

Start up with an external disk or cd then erase the internal drive and then install.

This is exactly what you will need to do.

Post #3 in this thread is exactly what you need to do. This works for Mavericks going forward, and IIRC, at the very least requires Lion or Mountain Lion to work. This is actually the method Apple sanctions.

When you get this and actually do the OS X installation, just be sure to use Disk Utility to remove any other partition you see there, and reformat the entire drive. From there, install on your reformatted internal drive, and off you go.

BL.

 

[Melissa Runnels]

Thanks, Bradl & nrubenstein!

I appreciate the detail & the link.

Melissa