Chosen Solution
Can you give this app a try: Temperature Gauge Pro. Snap a screenshot and post it here for us to see the thermal sensors and the fans RPM’s.
Check what I wrote in Faulty CPU/ODD sensors or fans after Dual Drive Kit Upgrade.
Same symptoms after SSD + new HD into a 21" mid-2011 iMac. I tried 3 other software products, none of which worked. BUT This one DOES work for me… CrystalIdea “Macs Fan Control” http://www.crystalidea.com/macs-fan-cont… Free, credible vendor (AFAIK). I have it set to sensor-based temp. control and auto-run on restart. Now the fans spin up to crazy speeds on reboot and as soon as Macs Fan Control starts, they slow right down. You can also use iStats Menus to put temperature display in the menu bar if you want to monitor the temps in your iMac. http://bjango.com/mac/istatmenus/ Hope that helps Richard
