My older iMac is running super slow. I am thinking of completely clearing the harddrive and starting over. Will that make any difference? Overview stats: iMac (24-inch Mid 2007) Processor: 2.4 GHz Intel Core 2 Duo, Memory 2 GB 667MHz, running Yosem

I would recommend against wiping the drive and starting over. What I would recommend before you do this is first increasing the RAM to 6GB or more. Although Yosemite 10.1.x can run on 2GB, that is the minimum system requirement. Increasing RAM may help substantially. However in order for us to make a more intelligent assessment it would be helpful if your posted an EtreCheck report of your computer and we can then look for obvious clues. You can download EtreCheck by clicking http://www.etresoft.com/etrecheck

It does not surprise me to see your Mac running slow with Yosemite. I would suggest to use Mavericks on this series and also max out the RAM. I also had a 2007 iMac just like yours and ran great with ML then started to show some age with Mavericks. I never installed Yosemite before upgrading to a new Mac so cannot compare with yours.

FWIW, unless you've downloaded Mavericks previously, it is no longer available at the app store.

And, on a system/hardware from 2007, personally I would not go past Snow Leopard (10.6.x) - it is a darn good OS and runs well with 2 GB of RAM.

Also note your remaining hard drive space: don't let it decrease much further - park some of your space hogging stuff on an external drive.

Another vote for upgrading the RAM. We have an early 2008 here that has only 4 GB, and it runs Mavericks pretty well. If you still experience a lot of sluggishness with more RAM, maybe you could install an intermediate OS version on an external drive, such as Mountain Lion (although that version costs $20).

Make a complete backup of your system and data to an external drive. You can migrate it back later. Then erase your drive, reinstall SL and upgrade to 10.6.8

Pete

I have a 2007 iMac running Yosemite without any problems.

I also have a new iMac, but still use the old iMac, since it has a DVD slot.

The HD has about 50% free space.

You should either trash or archive some of the data on the HD.

I was told by Apple that the 2007 iMac structure would not run Yosemite, and if it did it would eventually fail.

If it does fail I've kept a bootable copy of mountain lion on an external disc so I can always go back to that OS for this older iMac.

Frank Abramonte1 wrote:

I was told by Apple that the 2007 iMac structure would not run Yosemite, and if it did it would eventually fail.

If it does fail I've kept a bootable copy of mountain lion on an external disc so I can always go back to that OS for this older iMac.

I'm a bit curious about that advice from Apple: what kind of failure did they mean? Hardware?

As for keeping a bootable disk with an older OS, it's a very smart thing to do. Many of the problems reported here, including "upgrade remorse", could be avoided or fairly painlessly solved by having a good, bootable backup of a previous system. I have also made backups of the OS installer apps on flash drives, as well as saving copies of the installers on HDs.

I don't recall exactly what they said, just that it would fail.

Something about the architecture, or something like that which would prevent from running.

Previous to that, I had spoken to another Apple rep who didn't see any problems.

I thought if Yosemite installed and didn't get any error messages it would OK.

So far it's been about 6 months, and even though I don't use it every day, it's still working as it always did.

You may want to contact Apple, or post the question on the web.

How do I upgrade the ram?

The 2 places I’ve seen recommended most to buy reliable RAM are below. I have purchased RAM several times from Other World Computing and have always been very satisfied with the product and service. They have on-line instructions on how to replace the RAM. OWC has also tested RAM above what Apple states is the maximum. I now have 6GB installed on a machine supposedly limited to 4 GB.

Crucial

Other World Computing

Do a backup, preferably 2 separate ones on 2 separate drives.

Revert to a Previous OS X - Yosemite

Revert to Snow Leopard

If you do revert, I'd use Setup Assistant to restore your data. This process takes a while, so do it when you won't need the computer for several hours, based on my experience.

I use Carbon Copy Cloner which makes a bootable backup...not sure if other backups do the same.

Check before performing your backup.

Frank Abramonte1 wrote:

I use Carbon Copy Cloner which makes a bootable backup...not sure if other backups do the same.

Check before performing your backup.

CCC is probably the best option. SuperDuper also makes bootable backups, although not the recovery partition.