Hello, I just downloaded speedfan, because I wanted to try something other than HWmonitor (I love it, but I heard SpeedFan was better) so I was comparing core temps on my i5 750, and I was like what the h*ll is wrong with this.
Core 0: 31 C
Core 1: 31 C
Core 2: 34 C
Core 3: 28 C
Core 0: 20 C
Core 1: 18 C
Core 2: 21 C
Core 3: 13 C
all temps are idle, mobo is GA-P55A-UD4P heatsink hyper 212+ single fan and case HAF 922 stock fans
Personally i use HW because i too tried Speedfan and got goofy readings.
For accurate cpu temps i rely on Realtemp and Coretemp which on my rig give identical temps as does HW.
Needless to say i don't use Speedfan.