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Hardware InstallationHere is the picture of the tools I used to perform the upgrade (grounding wrist band, 6 Pc.
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The solution I adopted (found on several posts on the internet) was to replace the existing SATA HDD with an SSD, and replace the optical drive with a PATA to SATA adapter hosting a 2.5in HDD. So I wanted the fast SSD drive but also to maintain the 1 TB of space available. Here's also a You Tube video of someone installing an SSD in a 2008 iMac (somewhat similar to yours).I own a mid-2007 24in iMac with a 2.4 GHz Intel Core 2 Duo processor, 4GB of DDR2 DRAM, running Mac OS Mountain Lion, and for the past few months the computer was getting slower and slower, and when I was running Windows XP in VMWare Fusion, the machine was often swapping, bringing the iMac to a crawl. Finally I decided to upgrade my iMac by installing an SSD. Two years ago I replaced the Western Digital 500 GB hard drive (that failed on me one day by giving me the gray screen of death at boot time), with a 1 TB WD caviar green which I almost filled since then (about 750 GB used). This is just a standard hard drive replacement procedure (not an SSD swap)…but in steps 19-21 you can see what the temp.
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Here's a procedure (link below) describing how to replace the hard drive in a "Mid-2007" iMac. I think that your best bet (if you're super concerned).is to open the iMac up…and see what's in there. The only reason why the fans would go crazy…is if the temp sensor hardware was damaged…and the computer received no reading. I don't think that the fans will go crazy…since the with less heat & lower temp., there will be no reason for the fans to go crazy.
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