How accurate are fan controllers tempersture readings?

[chromic]

^--- topic, it has thermal , and should i keep the plastic "straws" around them?

 

[williamcummins]

The probes from fan controllers are pretty much accurate for ambient temps (like average temp inside your case). The problem is that you can't put those probes anywhere near the heat source of either your CPU or GPU. For CPU's and GPU's core temperature reading, you are better off with software like HWmonitor. A fan controller is still a good alternative when increasing the number of fans inside a system because most motherboard don't have more than 3 fan headers and therefor cannot all be controlled by BIOS.

 

[chromic]

My scythe kaze flat showed temperstures of :
(all in front of an cougar fan)

25.1c
25.3c
26.7c
26.1c

My samsung galaxy 4 temperature sensor showed ambient of ~24c