I don’t know. Probably not? If you try it, please write about it here. It would be cool to be able to make iMacs more sustainable by upgrading their processors only… I expect the performance equation is much more complicated that what processor you have…

Wow! respect for the soldering, and the upgrade! Thought that was a step too far by many accounts I read. Glad it worked for you. Good also to have the first rational explanation for the slow speed, but working mode it was in. Don’t think it can have been bent pins or whatever in my case… The limp-home mode seems totally plausible I think.

I replaced mine with a ssd in place of the optical drive as the boot drive, and a 4TB spinning drive for a bit of storage space.

I also needed to buy a thermal sensor from OWC to cause the fans to run at normal speeds.

- I bought Samsung 850 EVO 1TB 2.5-Inch SATA III Internal SSD (MZ-75E1T0B/AM) for the SSD.

- This is the spinning drive I bought: Western Digital WD4003FZEX WD 4TB Black SATAIII 64MB 7200RPM Desktop OEM-WD WD4003FZEX Black 4TB 7200RPM 64MB SATA 6Gbps Internal HDD OEM

- This is the thermal sensor I bought: OWC HD TCM Fan Control iMac 09-10

This combo worked for me. I suspect with the thermal sensor you can use whatever drive you want?

Not sure. I guess I must have cooked the old processor somehow? The old processor still worked but was SSSLLLLOOOOWWWW! I don't pretend to know how it all works in there, but I guess there must be some kind of error correction loop within the processor?

What I do know is that I did what you see in the guide, replacing the processor with a new identical one, and the computer is still working at the increased speed now almost 2 years later. it's a little steam-driven by modern standards, but still useful. $50 well spent!

I used a sharp kitchen knife to pry under the plastic ribbon at the right hand dot, then the left hand dot. Probably should have heated the adhesive, but my hairdryer is so clumsy... knife worked OK.

Bad luck. I did read on blogs some conjecture about weather the processor was socketed or not. It turned out it was socketed, which made it very easy to replace. All I was doing was replacing like-for-like processor. I wasn't trying to upgrade or anything. As you can see from the benchmarks even replacing like-for-like can be advantageous. (also inexpensive because these are not new processors now!)

Perhaps replacing your old processor with a fresh one of the same sort will improve things? It's worth a try if you got this far? It certainly worked for me. It's not fast by modern standards, but totally useable for a 7 year old machine is pretty good I think... Certainly never happened when I had windows machines!

Hi Cyndee, Creg,

Get the OWC thermal sensor. I didn't initially, and all the fans were working overtime the whole time. I tried software fixes, but they didn't work well enough. I eventually (months later) bought the OWC thermal sensor, re-opened my mac and installed. it. I'm back to having a pleasant, quiet mac.

Do yourself a favour and get the thermal sensor upfront.

Mark.