The original aluminum iMacs read the temperature of the hard drive through a simple stick-on thermistor.

Want to replace your hard drive? No problem, just peel the thermistor off of the old one and install it on the new one, and your iMac will be none the wiser. I did this on my own 20″ 2007 iMac with no ill effects. The next generation of iMac, the Late 2009 model, leveraged the temperature sensor that all manufacturers build into their drives (as part of the SMART diagnostic suite) instead of relying on an external sensor. The iMac read this value through a cable connected to the drive’s diagnostic serial connector, located next to the SATA connector. Each manufacturer uses a different style of diagnostic connector, so a vendor-specific cable is installed in these iMacs to match with the drive to be installed - if a Western Digital drive was going to be installed, a cable with a WD connector would also be installed, for example. Apple multi-sources its components, and so three such temperature cables exist, for use with WD, Seagate and Hitachi drives. Although later i noticed you could wedge the sharp edge of a knife between the glass and the case and widen the gap with a fingernail, then pull the glass out completely.Ī note when you're buying screw drivers.This means you can’t switch drive brands unless you also get your hands on the matching cable, and worse, you can’t connect any of the temperature cables to an SSD since they lack diagnostic connectors. Also used duct tape on edges of the container to create more friction and not damage the glass. Instead of buying suction cups, i used a vacuum cleaner inserted into the back of a plastic container to create more pressure per inch. I'm not here to rant though, i've some useful tips as well. Then randomly the installation fails and asks to try again. The installation starts and goes on for a while, while the hard drive makes a weird clicking noise. The problem i'm stuck with now is installing os x again.

My hd failed and i used this guide to replace it with the same model.

Internal hard drive for imac 2007