Works perfectly! This is a good option because the fan will still spin and the drive will be cooled. It’s only 1100RPM which is around the lowest speed for that fan which is fine for the hard drive or SSD. You can also use this method in conjunction with Macs Fan Control software or similar to raise and lower the speed based on the drive’s internal sensor if you wish. Yes, you can use JUST the fan control software but it will only turn on when the user is logged in; not a good option if you’re doing it for a customer who will probably query why their iMac sounds like a jet engine when it is starting up or sitting at the login screen. Some people suggest plugging the ODD sensor cable into the HDD sensor board connector. This is not a good idea because that fan cools the graphics card heatsink! You need that sensor working correctly. Just use the 1K resistor like Jigar suggests, on the HDD sensor cable. A touch of solder and some heat-shrink tubing and you’re good.