Easy Way to make quit yout PBO/Fan

[Dadi_oh]

Running FW P02 and associated bootcode .0202.0018 I measured 7V at the fan jumper. So a resitor of 100 Ohm did not let the fan start at all. If there are boxes with full 12V it may well be that this voltage can be controlled by the firmware.

Hmmm... Very interesting. So your box is putting out 7V to the fan unmodified? And you have the 12V version of the fan (written on the label)? That suggests Patriot is shipping some units with lower voltage to the fan to reduce the noise. And that suggests that Patriot is either able to change the voltage with changes to some components on the circuit board (resistors or jumpers) or... they can actually change the voltage from firmware.

I did download the beta FW but I better check using the play.pause trick.

Thanks for the info....

[VanDaPaul]

So your box is putting out 7V to the fan unmodified? And you have the 12V version of the fan (written on the label)?

2 x yes

I think the components directly located under the fan are the voltage converters, that normally also need some airflow, not only the DSP. My box now runs very silently with the 7V supplied and a 56 Ohm resistor and taped mounting of the fan. In addition I gave the sheet metal a little bend to get in close contact to the heatsink of the processor to get the heat conducted by the metal to the case.

[Dadi_oh]

2 x yes

I think the components directly located under the fan are the voltage converters, that normally also need some airflow, not only the DSP. My box now runs very silently with the 7V supplied and a 56 Ohm resistor and taped mounting of the fan. In addition I gave the sheet metal a little bend to get in close contact to the heatsink of the processor to get the heat conducted by the metal to the case.

Thanks for the info. So the box is putting out 7V at the fan connector and then you reduce it some more with a 56ohm resistor? That would be a 2.8V drop if the current was 50mA as written on the fan label. So your fan is actually receiving about 4.2V or did I misunderstand? Just wondering how low I could take my fan before it stalls.

And yes the power section also needs some cooling but power devices like FETs are usually rated to 150C or more on their junctions. I am less worried about them but if I can cool them even with the fan on ultra low speed that is desirable.

Cheers

[VanDaPaul]

I did not measure the actual current drawn by the fan, but the 50mA are given for a 12V supply. So it will be much less with 7V and the additional resistor.

[DuckieHo]

I just used a 4.3v, 5w Zener diode.... they give you more precise voltage restriction to the fan.

12v - 4.3v = 7.7v to the fan.

[billymm]

great tip Patrick thankyou

I just pulled mine completely apart & put heavy duty double sided tape between the fan & thin metal chassis.... I can hardly hear it now

Until I get hold of some better feet I cut a square (slightly larger than PBO) of rubber matting (like what is supplied under a motherboard in the box) & plonked the PBO on top

If only they had made the chassis out of slightly thicker sheetmetal where the fan is going to be mounted or provide a silicone gasket (sticky both sides to stop vibration) to go between chassis & fan

I intended to "top up" the oil in my fan since I had it out but it was completely sealed - I removed the label (to get to the oil filler hole) & it was all solid plastic

[tourist]

Now the noise on my unit is getting loud. I am about to do something with it. I'll try this way first. Thanks.