mid 2007 iMac processor upgrade

swordfish5736

macrumors 68000
Original poster
Jun 29, 2007
1,898
106
Cesspool
I got the urge the other day to do some fiddling with my iMac. Its a 24" 2.4ghz mid 07 model. The original aluminum. Ive had it since new. Replaced the hard drive once and upgraded it a second time so i've got no problem pulling the glass off to get to everything.

Last week i started doing research on upgrading the processor in this machine. After finding out it is in fact a socketed CPU I found out that i could at least upgrade to the "core 2 extreme" with a higher clock speed. Though also saw some mention of a newer penryn chip working. So i ordered up a T9300 off of ebay for 50 bucks. I just got everything buttoned back up and the machine does run. System profiler thinks its a 400mhz processor which sucks. However i ran geek bench on it before i took the old out and got a score of 3646 in 64-bit mode. I just ran it with the penryn process and got a score of 3716. Which makes me think while OS X and geebench think its only running at 400mhz its actually running at its 2.5ghz speed.

After some more research I've realized that the penryn iMacs use E class chips such as the E8235 2.8ghz chip. Im planning to pick up one of these and see if i can get any better/different results


Figured i'd share for those that may want to do something like this. It's really not that hard


here are the geek bench results
before:
http://browse.geekbench.ca/geekbench2/589034
after:
http://browse.geekbench.ca/geekbench2/589940
 
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swordfish5736

macrumors 68000
Original poster
Jun 29, 2007
1,898
106
Cesspool
Just thought i'd add i went ahead and ordered an intel E8435 chip. It's the 3.06ghz chip that came in the top of the line iMac in 08. I'll post results when I get it installed.


I've been running the machine with the T9300 for 2.5 days straight now on BOINC which basically runs the processor at full load unless I'm doing anything and my temps are actually a few degrees lower. I've also noticed an increased work being completed in BOINC and i haven't altered my usage on the machine so just one more indicator this chip is running at a higher clock speed than OS X thinks
 

swordfish5736

macrumors 68000
Original poster
Jun 29, 2007
1,898
106
Cesspool
Pretty cool. I have that same model and its feeling a bit sluggish. May be the perfect quick fix and hobby project.
yea its super easy to open the machine up I got a set of these: http://www.amazon.com/gp/product/B001PBQ9K8/ref=oh_o05_s01_i00_details

awhile ago and they make it very easy to pull the glass off. You can also swap the hard drive, optical drive or anything else while you are in there. I've thought about picking up a GPU from a newer iMac to see if that works as well but i figure I'll get the CPU stuff ironed out first.

and just noticed BOINC recognizes the intel chip at its full clock speed:
GenuineIntel
Intel(R) Core(TM)2 Duo CPU T9300 @ 2.50GHz [x86 Family 6 Model 23 Stepping 6]
(2 processors)
 
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elMacJunkie

macrumors newbie
Nov 13, 2007
5
0
tx
yea its super easy to open the machine up I got a set of these: http://www.amazon.com/gp/product/B001PBQ9K8/ref=oh_o05_s01_i00_details

awhile ago and they make it very easy to pull the glass off. You can also swap the hard drive, optical drive or anything else while you are in there. I've thought about picking up a GPU from a newer iMac to see if that works as well but i figure I'll get the CPU stuff ironed out first.

and just noticed BOINC recognizes the intel chip at its full clock speed:
GenuineIntel
Intel(R) Core(TM)2 Duo CPU T9300 @ 2.50GHz [x86 Family 6 Model 23 Stepping 6]
(2 processors)
Did you ever get it working with the intel E8435 chip ?
 

swordfish5736

macrumors 68000
Original poster
Jun 29, 2007
1,898
106
Cesspool
Did you ever get it working with the intel E8435 chip ?
I did not. I picked up a q9100 (quad core chip from around the same time) but was not able to get it to work.

I've been running the t9300 chip since march it runs slightly cooler than before. Geekbench scores are also slightly higher. I am on the fence about getting 6gb of ram(its pricey for this iMac) and an SSD.

if i do add an SSD i may find another cheap intel chip to throw in there while i've got the thing open. I think i spend more time cleaning the inside and outside of the glass and screen than i do actually working inside of it when i do open it.
 

t0p0ne

macrumors newbie
Aug 16, 2012
22
1
US to A
I did not. I picked up a q9100 (quad core chip from around the same time) but was not able to get it to work.

I've been running the t9300 chip since march it runs slightly cooler than before. Geekbench scores are also slightly higher. I am on the fence about getting 6gb of ram(its pricey for this iMac) and an SSD.

if i do add an SSD i may find another cheap intel chip to throw in there while i've got the thing open. I think i spend more time cleaning the inside and outside of the glass and screen than i do actually working inside of it when i do open it.
I was about to ask you the same thing with chip E8435 as i doubt it'd work because it's Socket/architecture than these T7500 T7700 T9300.. are socket T and i did tried a P socket chip P8600 @ 2.4Ghz and no go (no POST) and i guess try to snatch one T9300 later on Ebay :)
PS. i also get 400Mhz report with T8300 @ 2.4Ghz 3M 800Mhz haha that's so funny
 

canny

Suspended
Jun 11, 2009
141
524
I'm thinking of updating my old 2007 iMac with a T9300 chip. Does 10.12 and 10.13 beta work with this setup?
 

elf69

macrumors 68020
Jun 2, 2016
2,333
486
Cornwall UK
Sierra will run if you swap the CPU, just check ur wifi card as some are not sierra ready.
mine is not.

I got a 2007 20" imac and am going to do this mod with a T9300
i got 6gb ram it's £40 for 4GB stick in china or was when ordered mine.

You will need patcher to get the sierra install to work.
 

prizm

macrumors member
Oct 29, 2007
97
22
I too have a 2007. Already put a 500GB SSD in years ago. It still zooms along to this day. Seconds to boot up. Awesome. Id like to upgrade to Sierra as well. The T9300 is enticing. Do you know what the specs are on the Wifi card that I need?
 

elf69

macrumors 68020
Jun 2, 2016
2,333
486
Cornwall UK
yes you need:
Broadcom BCM94322MC from a macbook pro etc...

I know as I did the upgrade to a friends imac.
 

prizm

macrumors member
Oct 29, 2007
97
22
Thanks!
[doublepost=1496943364][/doublepost]
Sierra will run if you swap the CPU, just check ur wifi card as some are not sierra ready.
mine is not.

I got a 2007 20" imac and am going to do this mod with a T9300
i got 6gb ram it's £40 for 4GB stick in china or was when ordered mine.

You will need patcher to get the sierra install to work.
Do you know the type of ram you are using. Is it still the same ram from the original configuration when you purchased it? or after the chip swap can you get faster ram?
 

macadventurer

macrumors newbie
Jun 22, 2017
1
0
Hello guys. Im thinking about upgrading the CPU of 20 inch iMac 7,1. So even when the OS X thinks the T9300 isn’t running at it’s speed, it actually is, did i understand it right? Are there any similar bus speed and socket processors with higher speed, that somebody has tried?
 

canny

Suspended
Jun 11, 2009
141
524
For my mid-2007 24" iMac, I've ordered the:
  • T9300
  • Broadcom BCM94322MC
Do I still need a patch tool, or will the machine let me install Sierra normally?
 

canny

Suspended
Jun 11, 2009
141
524
need tool to patch it.
Trust me I did the sierra install for a friend, needs patching.

really easy though
Thanks, I will report back to confirm this worked.

BTW I'm guessing the dosdude patch will not work for high sierra, and there will need to be a separate patch.
 

elf69

macrumors 68020
Jun 2, 2016
2,333
486
Cornwall UK
unknown about high sierra.

but sierra enough for my friend and will be for me too when get round to doing it, just using it alot of late so not had chance upgrade it.
 

wilef

macrumors newbie
Aug 23, 2016
24
40
Thanks, I will report back to confirm this worked.

BTW I'm guessing the dosdude patch will not work for high sierra, and there will need to be a separate patch.
Canny, any luck? Any tips? Picked up this machine for $120 from someone locally who couldn't get it to boot anymore. I put 4GB ram inside and am installing to Snow Leopard right now. Once i get it squared away, I'm thinking of doing this as well. Would love to hear how Sierra runs and how challenging the swap was.
 

canny

Suspended
Jun 11, 2009
141
524
Canny, any luck? Any tips?
Yes, I got it working. Sierra with T9300 and new Broadcom.

There are a couple of problems.

The fans go on full throttle when the machine is running. This could be because I didn't put the machine back together properly, and didn't put the temperature probe thing in the right place (so it always thinks that it is hot). I use an app called Macs Fan Control which takes the fan speed down to a reasonable level.

The other issue is the volume - when headphones are not plugged in, it is always on full. Mute and volume controls don't affect it. Very annoying with auto playing videos. This can be 'solved' by plugging something into the headphone socket. With headphones, volume control and mute will work. (You could also use external speakers in the headphone socket of course)

I also have a partition running High Sierra with dosdudes HS-specific patch. This runs too slow to be usable, but there maybe updates to HS and the patch which make it worthwhile.
 

RG1955

macrumors newbie
Dec 14, 2017
1
0
same speed as original not faster.
2GB and 4GB, it came with 2x1GB when bought it.
If you are running 32 Bit OS, you would not notice the upgrade as 32 Bit only recognizes max 3 Gig Ram. If you are running 64 Bit OS, find something more challenging to test it
 

elf69

macrumors 68020
Jun 2, 2016
2,333
486
Cornwall UK
It will be 64bit when I upgrade it to High Sierra.

not done it yet as when tried my torx drivers are worn and do not bite so need go buy more.

but in about this Mac all 6GB is seen at present with El Capitan but did not notice if 64 or 32 version running.
 

rothomp3

macrumors newbie
Feb 27, 2018
1
0
Lake Monticello, VA
Hey just throwing another success report in here. I have a 20" mid-2007 iMac (iMac7,1) that I have put a T9300 in, and it works great. I'm running High Sierra on it, the WiFi card does not work and I have not replaced it, because the machine is located in a place where wired ethernet is available. With the latest dosdude patches, everything except the wifi card seems to work fine. macOS still reports 400MHz for the CPU and bus speed, but as above Geekbench results confirm that is only a display bug. One caveat to "everything works" is it does run afoul of High Sierra's buggy graphics stack from time to time, especially after the display has been turned off due to idle for a while. The GPU driver crashes, making it look like the machine is locked up, but if you log in via SSH everything is still working fine. If this happens to you, I suspect turning off display sleep is the easiest way to avoid it.

Now I desperately need to put an SSD in it, because the ancient 11 year old HDD is _really_ slow haha.
 
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