Looking to consolidate CPU Upgrade info for late 2009 Core 2 Duo iMacs in one thread.
As im sure many of you will be aware the base model late 2009 imacs ship with socket 775 E7600 and E8600. The E8600 is a solid upgrade over the E7600. But I feel we can do better.
Based on TDP limitations of the chassis 80w is most likely the limit without the iMac getting too loud or too hot. So here are some penryn 1333fsb 80w or lower CPU upgrades that can be considered:
X5270 (2x3.5ghz) (80w)
Q9550s (4x2.83ghz) (65w)
E5450 (4x3ghz) (80w)
Hardware wise the X5270 and E5450 are 771 CPUs, im not going to explain how/why these can work, because the 771 to 775 mod is all over the internet. All you need to know is that both the E5450 and X5270 can be bought with the adapter preinstalled.
Software wise the socket 775 late 2009 imacs don't appear to natively support any kind of penryn based quad core, there are accounts of people trying q9550s and other quad cores with none of them posting/chiming. Presumably this is due to some kind of acpi table limitation (not something I know much about).
So that takes me to my current attempt to get the X5270 working, which is basically an E8700, fundamentally its the same as the E8600 just slightly faster. Unfortunately simply swapping the B1 (775) microcode for the 44 (771) microcode doesn't do the trick, without the 775 microcode the imac refuses to post. You must have the 775 microcode somewhere in the first microcode slot for the imac to post, but if you try to run windows or macos with the 775 microcode it just gets hung-up and restarts.
The semi-solution to this is to have the 775 microcode and the 771 microcode. If you do that it posts, then it seems to try and switch to the 771 microcode. Which sort of works...?? Once it seemingly loads the 771 microcode you can then boot into windows.... but still not macos. But it gets weirder, the CPU is multiplier limited to 10x (3.33ghz), and is detected as X5260?????
Any input here would be greatly appreciated
As im sure many of you will be aware the base model late 2009 imacs ship with socket 775 E7600 and E8600. The E8600 is a solid upgrade over the E7600. But I feel we can do better.
Based on TDP limitations of the chassis 80w is most likely the limit without the iMac getting too loud or too hot. So here are some penryn 1333fsb 80w or lower CPU upgrades that can be considered:
X5270 (2x3.5ghz) (80w)
Q9550s (4x2.83ghz) (65w)
E5450 (4x3ghz) (80w)
Hardware wise the X5270 and E5450 are 771 CPUs, im not going to explain how/why these can work, because the 771 to 775 mod is all over the internet. All you need to know is that both the E5450 and X5270 can be bought with the adapter preinstalled.
Software wise the socket 775 late 2009 imacs don't appear to natively support any kind of penryn based quad core, there are accounts of people trying q9550s and other quad cores with none of them posting/chiming. Presumably this is due to some kind of acpi table limitation (not something I know much about).
So that takes me to my current attempt to get the X5270 working, which is basically an E8700, fundamentally its the same as the E8600 just slightly faster. Unfortunately simply swapping the B1 (775) microcode for the 44 (771) microcode doesn't do the trick, without the 775 microcode the imac refuses to post. You must have the 775 microcode somewhere in the first microcode slot for the imac to post, but if you try to run windows or macos with the 775 microcode it just gets hung-up and restarts.
The semi-solution to this is to have the 775 microcode and the 771 microcode. If you do that it posts, then it seems to try and switch to the 771 microcode. Which sort of works...?? Once it seemingly loads the 771 microcode you can then boot into windows.... but still not macos. But it gets weirder, the CPU is multiplier limited to 10x (3.33ghz), and is detected as X5260?????
Any input here would be greatly appreciated
