Chosen Solution
I have a late 2009 iMac with a slow E7600 CPU. I’m beginning to learn software development, and am focusing on the android side of mobile apps for the coming few months; however this will shift to iOS development after that. I am trying to setup my system to be good enough for compiling Xcode without wasting too much time. This is a shoe-string budget situation. If I had the funds, would purchase a new macbook/imac. I’m broke, and have been gifted this iMac as a start. Had an SSD lying around, and two additional 2GB modules, so it should suffice to start, but the CPU is just dinky. I can go from a C2D dual core to i7 quad core, theoretically, by exchanging the logic boards. They appear to be the same physical dimensions based on the pictures I’ve seen of both. Is this correct? I’ve already opened her up to replace the 3.5" with an SSD. Not an issue doing the surgery. My question is if this is technically feasible. I understand there is a TDP difference of 30 watts, but am willing to give it a go as my current CPU barely registers a temp differential between idle and several minutes of Prime95 load. It appears there’s headroom here with the current cooling solution. Are there, for instance, physical connectors which will be differing? The logic boards appear to be had for less than $100 if you look deep enough. I want to do this in the coming weeks, but can’t afford a waste of an investment. Can I have success here? Stories to back up the claims by chance? I couldn’t find anything on upgrading logic boards. Perhaps this is around I just didn’t dig enough? It seems they use the same power supply, and upon inspection of the images further, the same connectors as well. I will attempt this if someone can’t provide reason why not.
Before we go into the CPU you do have an issue with the HDD to SSD swap out. You need this: OWC In-line Digital Thermal Sensor for iMac 2009-2010 Hard Drive Upgrade If you review the IFIXIT guide here: iMac Intel 27" EMC 2309 and 2374 Hard Drive Replacement take note of Step10 your SSD doesn’t have an onboard thermal sensor for the systems heat management (SMC) to access. So your system will go into safe mode racing the fans as it wants to make sure your system doesn’t overheat. Depending on what your exact system is we do have a IFIXIT guide to upgrade the CPU! Here’s the guide: iMac 27" Late 2009 Intel Processor Replacement (EMC 2374) You do need to get the correct chip! It’s going to take some effort to find one.
That took forever! First the guy selling the logic board went on vaca, then the board he sent was broken in a way that was totally different from the pics. Had to ship it out of state to get the LVDS repaired. Guy caught the flu and was out of commission for 12 days since the board arrived. Finally got it back and it works! It shows up as an i7-870 but this is a Xeon X3470. My brother still has his CPU and I needed a solution. Only $35 online. I got the single extra sensor that was the difference, ran it up behind the camera. Also put in a new battery. Geekbench shows a jump from 3K to 9.3K multicore score. I’m happy and have decided against messing with overclocking. Temps are fine I’m using the fan control to ensure it caps out in low 80s. In reality it’ll rarely if ever hit that high, that’s with prime95 hammering it. The only issue I had was the board was stuck on digital audio. I tried blowing in it, sifting around with a toothpick, and using a Q-tip with rubbing alcohol. Using the flash on my phone, it looks quite clean, but still didn’t work. So I got a cheap usb audio card. Fully functioning upgrade =)
