I’m tied of the poor performance of the HDD in my iMac 27” mid-2015 and so ordered an adhesive replacement kit and a Samsung 1 TB SSD. I’m ready to take it on, worts and all but can’t seem to find a definitive answer to if I need a thermal sensor or not. I can find information about the late-2015 not requiring one but can’t find anything about the mid-2015. Any advice would be appreciated. Thanks
iMac Line (2012 and Later)
I recommend you buy and use the kit with the thermal sensor.
Without knowing which macOS version you're running, we cannot advise on the veracity of the claims of improved fan management. It's would be best to err on the side of including a sensor, than not to and then have to spend time troubleshooting another problem.
Per this vid at OWC, the 27" iMac (2012 - 2019) uses the sensor on the HD. When replacing the HD on those units the sensor replacement should be mounted on the new SSD.
See video > https://eshop.macsales.com/installvideos/imac_27in5k_14late_hdd/ (see comments starting at at 05:30)
I recommend you buy and use the kit with the thermal sensor.
Without knowing which macOS version you're running, we cannot advise on the veracity of the claims of improved fan management. It's would be best to err on the side of including a sensor, than not to and then have to spend time troubleshooting another problem.
Per this vid at OWC, the 27" iMac (2012 - 2019) uses the sensor on the HD. When replacing the HD on those units the sensor replacement should be mounted on the new SSD.
See video > https://eshop.macsales.com/installvideos/imac_27in5k_14late_hdd/ (see comments starting at at 05:30)
OWC's upgrade page mentions a thermal sensor in the kit for the iMac 27" 2013-2019 models. I don't know if all those models require the thermal sensor or just some of the earlier models as it may be easier for OWC to sell just a single kit than having several kits. From what I've seen of Apple, I would want to have the thermal sensor when performing the upgrade especially since OWC includes it in the kit for the 2015 iMac.
https://eshop.macsales.com/shop/ssd/owc/imac-27-inch/2013-2019
For as far as I know You need a thermal sensor if you want to do this.
Replacing the HDD is not recommended by Apple so doing so will be at your own risk.
I recently updated a 2013 with an SSD. I purchased all the required parts at OWC. The kit included the adhesive kit, AdaptaDrive, SSD, tools and inline thermal sensor.
https://eshop.macsales.com/installvideos/imac-27-inch-5k-late-2015/
Welcome to Apple Support Community.
Please consider to use an external SSD: How to Setup and Use an External SSD as y… - Apple Community. It has no risk to install since it's connected via USB, with almost identical performance.
I've been running my iMac (21.5-inch, Late 2015) from an external SSD for over a year now and have had no issues.
Jack
Thanks stedman1, I’ve seen that and similar kits. I’m trying to confirm though, if the thermal sensor is a must. I’ve read that the MacOS has been updated with smarts to handle the fans better without the need of a sensor.
iMac 27” mid 2015 SSD upgrade, is a thermal sensor needed?
