I only like one kind
WOW! they really listen around here, some one reads these boards.
I went on AMazon today and poof there is the passive heatsink, it wasnt on there before or i would of already ordered one not that i dont want to order from Khadas at this time i dont trust my PC. Since ive been messing with Roms and the toolds to install them ive had to go to some very shady sites to get these files and i just dont think my machine is safe at this moment and i dont wan to use it for any kind of purchase but the amazon site has everything saved so i just clock it and its already linked to banking info so i dont have to type out anything. I think Amazon is linked to Khadas anyway because it says âseller: Khadasâ so its not a third party seller anyway.
Now if we could get a sink that sits directly on the CPU the thermal pads on the other chips i dont mind i just prefer direct contact sink to the CPU and thermal paste rather then a flat gummy bear 
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@BowerR64 your reason is here,
Donât worry they put them in stock before you even asked 
You would need something to mount the heatsink to, it is not like our regular PC itx/atx motherboards, where we have standard heatsink/cooling solution mounts like these,
as @birty suggested, you could use some Thermal epoxy to stick it on to the CPU, but note, it will be a one time procedure, you probably wonât be able to take it off, otherwise taking the applied heatsink would rip the CPU from the PCB with it 
Are we talking Haribo or black forest organic ???
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LOL, which ever smells the best went they get cooking?
I think it just needs to be milled a little more so there is direct contact to just the CPU we can use the gummy bears for the other chips if they even need it, im wondering if the heat from the CPU isnt transfering from the CPU back down into the ram and rom chips and making them run hotter then they do if they wernt even touching the sink to begin with?
I may have to try that? remove the pads and run a few stack of these copper pads i have and lift the sink up anough so that its just sitting on the CPU and nothing else and see if theres any improvement
If you were going to add shims and try to raise the heatsink (as to having it sit over all the components, you might want to get some Taller screws, and attach some small springs on each screw,
it would kind of look like thisâŚ
They would provide necessary force on the CPU without bending or damaging the boardâŚ
do they make springs and srews small enough to fit threw the holes on the vim sink?
What about longer case screws so i can cram a 40mmX20mm Noctua 3D printer fan under the lid? or a 40X10
I wish the 5V line on the I/O pins powered with the OS, when android powers down those pins shut off also
a quick search on amazon should do the trickâŚ
well I have a 40x40x20mm fan on my VIM3, lemme show you a pic, you can get a reference size, it kinda fitsâŚ
Here is is snugly fit in the gap where the stock fan is supposed to be, it fits well but there would be no airflow
You could put it on top like i did here, which is the best way for cooling but nothing is keeping it fixedâŚ
Two Words: Krescue and KBI
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Got some links i can read about this?
What pins are used?
Your fan setup doesnt look right, is it blowing out or into the sink?
I thought you needed a gap for the air to move threw?
I thought, in which box should I put it as a DIY cover for the board?
Here you go, this should help : https://docs.khadas.com/vim3/KbiGuidance.html
GPIO 1, 21 as +,- respectively for 5v
GPIO 20, 40 as +,- respectively for 3.3v
if you need less noise go for lower voltage, but since these Fans donât even whisper, they are practically silent, so I always go for 5v, but 3.3v is good is the device is just Idle at timesâŚ
Yeah, this particular fan is a bit bigger, so I usually use Picture #3 as the setup, It wiggles around due the force of spinning (Inertia and Newtonâs 3rd Law)
It blows air directly on to the Heatsink, The top is the intake, It does quite a good job,
If you are interested in non-Stock Fan for cooling you can get that Noctua Mini 40x40mm 5v Fan
But here is some of my other recommendations
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do you want to try the conky cardboard case ???
iâm joking, buddy!
No, Iâm serious, 
if you guys are interested I will post the 2D design files for it, #Opensource
I think, no one will mind
I already have 2 Noctua fans, both are 40X40, one is 20mm thick the other is 10mm
The 20mm thick one seems to move more air
Yeah, it is because of the larger Wingspan areaâŚ
I love that fan, I used to have one but now I donât, here in my country it is wayy tooo expensive so I went for a offbrand one, quite similar, with a high airflow and is silent, still happy with it.
Nidec fans are also quite good, infact I see that khadas stock fan is manufactured by Nidec themselves
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its an ugly color but it has all the stuff with it to connect it to different things, an extension lead and the splitter if you need to cut the wires and splice it.
I wish it could be controlled threw the board like the stock fan, ide like to ramp it up at times. Saying playing games, benchmarks, watching HD videos but at other times kick it back down to a whisper
It has 4 leads like the Khadas fan but i dont think it does the same i think its just to monitor RPMs
Yep, those PWM fans utilize a different control mechanism, If you studied about it for a while, I bet you could make it work, emulating it with the GPIO pins onboard the device
There isnt already a discussion page about it?
You mean im the first to use a differnet fan for one of these and use the OS to control it?
That seems odd
Hey guys I was just pondering upon this topic, when I saw this researcher who was trying to see whether specific heatsinks would benefit from having a different type of fin stack, which lead me to come to the assumption, many of the existing blower-style heatsinks suck. here is why,
One of the apparent super powers of centrifugal fans is the ability to have a greater static pressure, in laymanâs terms, it applies more pressure to air, allowing it to go through complex paths and overcome turbulence,
when this fan is used with fin stacks perpendicular to the flow of air, it wastes the apparent superpower and seems like the heatsink wonât work but in reality, it is compensated by the low air speed which means it give time for the air at the surface of the heatsink to heat up and create thermal equilibrium,
but, what if I told you, there is a way to improve the efficiency of such heatsinksâŚ
take a look here, these are some diagrams for the different fin arrangements that can increase the efficiency,
- represents the normal heatsink fin stack
- represents the other types of possible fin designs
here is what happens to the moving air along the surface of regular fins (1.) in narrow channels,
it is going at different speeds along the fin surface, defined as fluid velocity difference in a channel
these create the irregularity in the air flow, causing air in the center of the channel, to not be heated, but move out very quickly, whereas air at the surfaces get dragged and have time to absorb heat, but they ae so slow that the heat is dissipated, at a very slow paceâŚ
âŚ
Now coming to the advantage provided in the different fin stack pattern, these have slight variations in the path of the airflow, causing the air to get a bit turbulent and create mixing, this mixing property, (probably attributed to vortex formation), replaces the air at the fin surface and allow it to be heated by the heatsink to get evenly distributed, resulting in more effective cooling,
(wavy airflow, which bounces along the side of the fin surfaces, increasing heat transfer efficiency
Now, I am not a professional engineer, and my knowledge may be limited, but this is my theoretical assumption based on my knowledge of basic fluid dynamicsâŚ
If there is anyone who can back my theory I am more than welcome to accept it, I am also a in the stage of knowledge development, so my knowledge only grows stronger on tips and constructive criticism 
Some useful links:
https://www.researchgate.net/figure/Staggered-and-In-line-Finned-Heat-Sinks_fig4_267597461
and
I hope this will be found useful, If you think my idea is innovative and has potential, it would be helpful you can test this in a design suite or make a functional prototype, it would be grateful
Cheers!
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