iMac 27 i5 2.7 mid 2011: Upgrade CPU to i7 2600 (non K)

[xserban]

Hi guys and thank you so much for the valuable information on this forum. I've researched a lot but still have some questions that I need your expert feedback on.

I was wondering if any of you who have managed to upgrade the i5 2.7 CPU to the i7 2600 CPU in the 27" iMacs have ever had problems. I would be interested to know the following:

1. how long have you used the machine for with the upgrade?
2. are you using CPU intensive software light lightroom / media encoder / photoshop or high res games?
3. has the system been as stable as before until now?
4. has the mac been noisier or much more hot?
5. do you happen to know if the PSU and cooling components in the the i5 and I7 iMacs as sold by Apple are the same?

Thanks a ton.

 

[xserban]

Anyone knows anything about the questions above?

Thanks in advance

 

[ChristianVirtual]

I'm not sure if you could/should put a desktop CPU into an iMac. I recently rebuild my server and put in a i7 2600S; even that one has a hell of a CPU cooler.
No way that would fit into imac without cutting a whole in the back.

Did you found somewhere a hint that someone replaced a CPU ? Successfully ?

Did you looked at www.ifixit.com ? They might have some more hint; seems the CPU sits on a socket so physically possible.

 

[The-Pro]

I'm not sure if you could/should put a desktop CPU into an iMac. I recently rebuild my server and put in a i7 2600S; even that oe has a hell of a CPU cooler.
No way that would fit into imac without utting a whole in the back.

Did you found somewhere a hint that someone replaced a CPU ? Successfully ?

iMac CPU's are desktop CPU's allready. The update he is talking about was technically offered by apple as a BTO.
People have managed to upgrade to the i7.

 

[ChristianVirtual]

iMac CPU's are desktop CPU's allready. They update he is talking about was technically offered by apple as a BTO.
People have managed to upgrade to the i7.

With regular i7 ? That one would have 95W TPD; the S version only 65W.
I know that BTO with i7 is ok; have one on my desk. But I never bothered to check what CPU variant they use. Will do when home.

I would be concerned about the cooling /thermal design. But hey, happy to be corrected and see example where it really works.

 

[The-Pro]

With regular i7 ? That one would have 95W TPD; the S version only 65W.
I know that BTO with i7 is ok; have one on my desk. But I never bothered to check what CPU variant they use. Will do when home.

I would be concerned about the cooling /thermal design. But hey, happy to be corrected and see example where it really works.

Yeah.
Im pretty sure that in the 27" the 3.4GHz upgrade was the i7 2600. In the 21.5" the upgrade to the 2.8 i7 was the 2600S.
Haha, I didn't see your signature

This user upgraded to the 2700:
https://forums.macrumors.com/threads/1323028/

 

[xserban]

Thank you guys. Don't want to sound rude but I was actually expecting replies from someone who actually got it working and can reply to my initial questions.

Indeed the 2600 has a TDP of 95W while my i5 CPU currently inside has 65W. This is a big difference. I also have a 2600K PC with a heatsink so large that I can't close the lid (4.5 Ghz)...I know all this, I need advice from someone who made it

 

[wmy5]

Thank you guys. Don't want to sound rude but I was actually expecting replies from someone who actually got it working and can reply to my initial questions.

Indeed the 2600 has a TDP of 95W while my i5 CPU currently inside has 65W. This is a big difference. I also have a 2600K PC with a heatsink so large that I can't close the lid (4.5 Ghz)...I know all this, I need advice from someone who made it

I have a 27" iMac with i5 750 (Late 2009) and I upgraded with i7 870 by myself. 27" model has no problem with 95W TDP, you will be fine with 2600 or 2700. If you have 21.5" iMac, go with the CPU with S.

 

[thekev]

With regular i7 ? That one would have 95W TPD; the S version only 65W.
I know that BTO with i7 is ok; have one on my desk. But I never bothered to check what CPU variant they use. Will do when home.

I would be concerned about the cooling /thermal design. But hey, happy to be corrected and see example where it really works.

They are the 95W versions. The ivy bridge versions top out at 77W. In both cases after that point it moves to a different socket type. A lot of Apple's designs are impacted by thermal constraints. I'll be interested to see how they handle it in the new imacs. Also ifixit says the same thing.

 

[xserban]

thanks, still waiting for that someone who made it

 

[The-Pro]

thanks, still waiting for that someone who made it

The link i posted earlier is from someone who made it with an i7 2700. Quite possible that its as close as you will get. If the 2700 works well, like the user said, then the 2600 will work aswell.

 

[xserban]

Well, I made it today. Traded the 2600K in my win machine for a regular 2600. Disassembled the imac following the excellent OWC guide that's available on youtube. Switched the CPUS, put it all back and turned it on:

in the following, I'm taling in the metric system, by degrees I understand centigrades and not Fahrenheit.

it booted into Mountain Lion, the system reported the new cpu correctly as i7 2600. Since I was worried about temperatures, decided to stress it for a while using prime 95. Ran prime95 for 5 minutes, cpu was under 70 degrees (mac sensor I would think) since the internal cores (die) seemed to be at 90 degrees. (used this one: http://www.bresink.de/osx/TemperatureMonitor.html)

Stopped prime 95 and browsed around for a while then decided to run geekbench. Got a nice score of 11700 and then while chatting with a friend I decided to run prime 95 again and let it stress my cpu even more.

Kept in running for 10-15 minutes, the system was stable, fans were pretty quiet, same 69 degrees reported (87 - 92 in the cores). Turned off prime95 once again and in about a minute or so, my system turned off all of a sudden. From nice OSX desktop to pitch black.

Tried to restart it with no luck for the next minute, then the system started, the screen was gray with the apple boot logo, the fans were spinning like crazy, the air vented at the top like mad. The boot halted to black screen and instant power off.
Managed to start it a few more times to the same result. And then it didn't want to start anymore.
I pulled the plug and waited for around an hour then tried again. Nothing. Machine is dead cold.

Tried to press the button for 5 seconds or 30 seconds with or without cable. Nada. Tried command shift p r, nothing.

I thought that the guy that traded his cpu stinged me with a broken one so I thought to test it in my win machine. Disassembled the imac again (muuuch faster this time), long story short, I'm now writing from the win machine using the 2600 cpu, and it just finished encoding a movie with all 8 virtual cores at 99% load.... so cpu is fine....

thoughts?

(yeah, I know, don't DIY a mac, good lesson, already learnt)