Will Yosemite run on iMac Early 2008

Yes: http://www.apple.com/osx/how-to-upgrade/

See first section in that page.

Whoops, somehow I read the question as "is it compatible?"...

I personally always update to the latest even if there's a performance penalty. Reason: compatibility with new software and security. Staying with Mavericks will only get you security updates for perhaps another 1 year.

I installed Yosemite in a Macbook Pro Core 2 Duo 2,4Ghz. I did see a small slow down, but not significant enough to disturb. In your case, I'd only install if you upgrade your RAM to 8GB and maybe replace HDD with SSD.

You can always clone the HDD with Carbon Copy Cloner, install Yosemite on computer, test-drive and, if not happy, use backup to restore Mavericks.

I'd try to understand Carbon Copy Cloner first on my own, it's rather simple. If unclear, this article should be of help: https://bombich.com/kb/ccc4/i-want-clone-my-entire-hard-drive-new-hard-drive-or- new-machine

I installed Yosemite on a Mid 2007 iMac with 4GB Ram and a regular mechanical drive, and all works fine. Its not Blazingly fast, but its also not dragging. It works perfectly well. some Apps take longer to open than others. But for usual Tasks its pretty quick

So while the ssd may give you performance enhancement and the extra Ram is very recommendable, neither should be necessary.

I have the same question: I have an early 2008 iMac 8,1, 24 inch, Intel core 2 duo 2.8 Ghz, with 4 GB RAM. I've been running Snow Leopard for years and want to update my system. The machine itself is fine. It's a 320 GB hard drive and I appear to have about 50 GB available.

Can I handle Yosemite? Also, I know some are saying it can take up to 6GB, but when I was upgrading to 4, I did a check somewhere online that told me 4 was my max.

If I can upgrade, does Yosemite make more sense than Mavericks--and what, other than backing up, do I need to do to prepare?

Thanks,
Joanne

Jazzo,

I have a late 2007 Mac (7,1) and I increased the ram to 6 GB. There were several responses that even tho Apple says 4, you can do it if you use either Crucial memory or memory purchased thru OWS. I have been running 6 GB for about 5 months and the increase in speed is noticeable. After my HD failed last week I had it replaced with a 1 TB and I have full access to that. I have a local Apple repair facility here in Tucson that has been here longer than our Apple store and I have used them several times.

Homer

Your Mac should be able to handle Yosemite just fine.

Additionally to a Backup, you may want to check if your current Apps will run under Yosemite. If you have older apps that require PPC support they may not run.

Check your applications for compatibility

Your Mac can take up to 6GB of good quality, Mac tested RAM.

http://eshop.macsales.com/shop/memory/iMac/Intel_Core_2_Duo_PC2-6400

Thanks, guys, this is very encouraging. When we upgraded to 4 MB of RAM several years ago, we did it with Crucial, running the serial number through their site and buying the max upgrade, which they said was 2.

So OWS is sure it can really take another 2 even if Apple and Crucial say no?

I'm a little gun shy about this, since the only other time I tried to upgrade a system, an original green iMac in 2004, it turned into a door stop.

This is my husband's computer: I have an early 2009 with 8 MB of RAM, so I think I'm probably in better shape.

One more question: is 50 GB enough room on his hard drive?

Thanks in advance!
Joanne

Yes. OWC guarantees their RAM, and test the amounts they publish thoroughly in the computers they mention wok with them.

From their website:

As to the 50GB. Its a little on the low side, but not too bad. You'll be able to install Yosemite fine with that, but you may want to make some room anyway, by deleting older stuff you don't need, or moving some files out to an external hard drive if you can.

I've been a customer of OWC for years and have bought several sets of RAM from them (my first two upgrades and then this one to 6 GB). If they could figure out how to get 8 GB on my Mac, I would buy it.

If you have stuff on your Mac you want to keep, you can always get an inexpensive external hard drive and use that. I have a 1TB drive on my system where I keep reference materials to give me some space on my drive. Now that I replaced my original 320 GB drive with a 1 TB drive, I don't really need it, but it will stay there. I had to replace my drive when it failed after 7+ years of flawless operations. The company I used also gave me back my old drive so I can play with it.

Homer

Thank you everyone for the great advice. I just ordered a 4 GB memory card to replace the 2 GB I put in a few years ago, giving me a total of 6. Once that's done, I will back up in every conceivable way and take the plunge into Yosemite!

I really appreciate all your replies.

Joanne

Did your hard drive give you any warning before it crapped out?

Nope. I had Postbox (email program) and Chrome open and the system froze. I had to restart and got the Flashing file folder of death. Couldn't get into Safe Mode or the Recovery partition. I took it to a place in Tucson that has been the Apple dealer before Apple came to town. Took it in on a Wed afternoon, they called me on Thursday and said it was the hard drive and it was ready on Friday. Had the option of 500 GB or 1TB so I went with the 1TB for $25 more. What was really great, they even gave me the steps to restore from my Time Machine backup. That is customer service.

I have a TM backup as well as Carbonite and I restored from TM. Took me about an hour once I got everything plugged back it.