I indeed took power straight from the PSU (I'm still using the standard Enermax GX850 PSU). Pulling ~700watt at the wall, so plenty of room for the 2 fans.
This options:
--avalon-invert-pwm --avalon-fan 30-90 --avalon-fanwait 5 --avalon-fanfactor 160
--avalon-invert-pwm --avalon-fan 99-100 --avalon-fanfactor 160
--avalon-invert-pwm --avalon-fan 9-10 --avalon-fanfactor 160
--avalon-fan 99-100 --avalon-fanfactor 160
--avalon-fan 9-10 --avalon-fanfactor 160
Give me those readings:
Status MHS5s MinerCount AsicCount Frequency Fan1 Fan2 Fan3 Temp1 Temp2 Temp3 NMW Firmware
Alive 79276.71 24 10 350 0 2720 2720 34 52 54 10 20130714
Alive 85793.17 24 10 350 0 2560 2560 35 56 57 4 20130714
Alive 73036.38 24 10 350 0 0 0 36 56 58 2 20130714
Alive 64177.27 24 10 350 0 0 0 36 57 59 0 20130714
Alive 1823.91 24 10 350 0 1920 1920 36 57 59 0 20130714
Extended the fan cable, because the original was only 5cm. I even redid it and use thicker cable:

Can this somehow cause incorrect readings on the sense- or control-wire?