Quote:
Originally posted by pHaestus
The temp never changed with a homemade diode reader however.
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Would expect a small effect.
Maybe* this type of behaviour for a 100watt** CPU with a very good waterblock( "C/W"= Rwb= 0.2c/w) :-
Cwb= Wt*Rwb - (Rwb/Rmb)*Cmb
* From this arithmetic :-
Wt=Wwb + Wmb, Rmb = Cmb/Wmb, Rwb= Cwb/Wwb
Where Wt=Total Heat output, Wwb=Heat Dissipated Thro wb, Wmb=Heat Dissipated Thro Secondary Paths(probably motherboard(mb)), Rwb=Thermal Resistance of wb(inc TIM), Rmb= Thermal Resistance of Secondary Paths(probably mb), Cmb= Temp Difference between Die and Secondary Heatsink, and Cwb= Temp Difference between Die and Water..
Clumsy maninipulation and substitution[Wt/Cwb = Wwb/Cwb + Wmb/Cwb , Wt/Cwb = Wwb/Cwb + Cmb/Rmb x 1/Cwb = 1/Rwb + Cmb/Cwb x 1/Rmb, Cwb = Wt/(Wwb/Cwb + Cmb/Rmb x Cwb, Cwb= Wt/(1/Rwb + Cmb/Cwb(1/Rmb), Cwb/Rwb + Cmb/Rmb = Wt ] gives:-
Cwb= Wt*Rwb - (Rwb/Rmb)*Cmb
** I am still open minded the apparent discrepancy between CPU heat calculations and reality. Do not think it is anywhere near established how much is due to "crap sums and crap CPU stress programs" and how much is due to secondary heat-paths.