There are kits that have a thermal circuit and plug between the hard drive and cables to the 3.5" drive to allow other non-apple drives to be installed and still have the fans and diagnostics function normally. No need to short or modify fan speed with software that won't adjust for temperature properly. You just attach the thermal sensor to the drive and plug it in. Usually range from $50-$80 just for the cable, I'm really shocked I can't find them available from ifixit! Just ordered one from the US source.