No, that is not possible. Would also make not much sense for fan control since the internal sensors jump up and down within seconds.
The CPU/GPU temp fluctuation is definitely higher than the coolant but I wouldn't say it's useless in controlling fan speed. I've been using these parameters for watercooling successfully for quite a while.
Phil
i7 4GHz ♦ Asus R2G ♦ OCZ Intel XMP ♦ Asus 5870 ♦ Crucial M4 ♦ Swiftech ♦ Koolance
X4 3.5GHz ♦ Biostar 890GXE ♦ OCZ AMD BE ♦ Asus 8800 ♦ WD Veloci ♦ Swiftech ♦ XSPC
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