Vim 3 Alloy Case as found and others

Nice, decent results for a passively cooled case,
expect a bit more for a case that’s made entirely of Aluminium,
but the bottom part is left in open air, not contacting anything right ?, maybe a heat pad could help just a bit and ease the max performance at 90%

Forgot to mention :upside_down_face:
I do have a thermal pad in the Bottom but not thick enuff I feel to do a lot of good.
The base plate shows no buldge presently, its not squeezed in tight enough, need to add a thin piece
Long as you keep the box elevated even with even larger rubbber feet than supplied you would get good if not better thermal dynamics good air flow is the Key,
Forced air is good but as we know Noise and dust get in eventually

15 minutes flat chat something you would not normally do,
I have seen others Hotter doing far less.

What is there on the bottom though ?, like if we flip the case we can see the side where there processer meets the projected part from case is that part Hollow or a solid chuck of metal ?

You can see the base plate, one with two mounting holes and 4 post

If you plan to use the two mounting holes BEWARE the base/underside of the PCB is close
would hate to see a metal screw head short out the bits and let the magic smoke out

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Pardon my blender skills :grin:


image
I assume that you can see the circled part representing the part that contacts the CPU, is that Hollow or a chunk of Metal?

Also I wanted to point out that, a few weeks ago I was benchmarking the VIM3 topic here

I got Temps that were similar to yours, in the 70 to 75 degrees, but my Graph looked a bit different,


Any idea why ?
note it was actively cooled but the Temp was almost same

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Not sure why the difference in the graph,
Apps running in the backround, position of the planets.
Bechmarking has its own rules:
Its all just to give an idea basically

yes that block is part of the case Lid and that fine piece of artwork (looks ok to me)

The Thermal pad supplied covers CPU and Ram.

Thank you Robert.

So it looks like fully loading just two cores gets CPU into thermal throttling pretty quickly with this case. [EDIT: Oh I may have misread the graph. Are the four big cores fully loaded?] The VIM3 puts put too much thermal energy for a flat case to dissipate and this supports the idea that radiator fins should have been part of the mould.

By comparison i can load all 6 cores at ~80% with mpv video player, and stay in the 72-74C range, despite the base not mating properly with the CPU.

It should be possible to get even better results than my MacGyver case by attaching a large heatsink to the exterior of the KKSB case on the CPU side.

While it might be too expensive for KKSB to make a new case mould, perhaps they could offer a deluxe version with a heatsink screwed on to the hot side of the case.

Cheers.

Whoah! That’s a big heatsink :smiley:,
How good are your temps ?

As I wrote in my post, mpv with fullscreen gives me 72-74 degrees celsius max.

Additionally:

  • Compiling with 6 cores gets me around 52-67 degrees celsius.
  • Converting video with ffmpeg (default multi-core) gets me to around 55-62 degrees.
  • Doing both at once gets me to around 72 degrees celsius.
  • A cpu-burn program with all 6 cores at 100% gets me over 75 degrees, triggering throttling.
  • Idle temps are around 39 degrees celsius, which is pretty high compared to my similarly cooled jetson nano which idles at 32 degrees celsius because it has no thermal pads between heatsink and cpu die.

The two main heat bottlenecks are

  • The interface between board and heatsink consists of thermal pads, because i cannot CNC-lathe a matching baseplate. This is a big bottleneck, and is somewhat compensated by the oversize heatsink which stays quite cool and gives me a better transfer across the pads.
  • The cardboard box around the bottom of the board traps heat. A metal case with heat-conducting pads on the underside of the board would help wick-away more heat.

My solution is fanless, cost me only a couple euro, and doesn’t get into throttling with real-world loads. I’d love a prettier case but I can’t justify spending more on it.

[EDIT] I just discovered that mounting the VIM3 vertically gives me 3-4 degrees lower temps, probably due to an improved convection (chimney effect) through the fins.

yep, definitely, since just a passive heatpipe and fins won’t acehive much need to use a, a small fan to push out hot air through it and cool that puppy down :slight_smile:

I don’t need a fan to avoid throttling in real world aplicatons.

I am curious if the case featured by OP does.

Not 100% sure with the software used, gives you an idea it should handle most,
As you say more Heat sink/fins on top, and even on the underside mount side ways
The Chimney effect should fairly easy to do, but would adds to cost of production I guess

As an option for the avid user the KKSB would do fine.

You could easy with two blocks of alloy 5 to 10mm thick, some thermal Pad and sandwich the Vim PCB bolt the two together mount vertical, maybe cut around the GPIO pins to gain access

It may not Look as Pretty but when you are decoding stuff, beauty is in the eye of the beholder,
If its 100% efficient don’t really care what it looks like.
:+1:

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And not to forget Khadas have just released

Might be fun :slight_smile:

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sweet heatsink !, guess it should keep the VIM nice and cool, and silent,

But I wish for one that has, a vapor chamber or heatpipe to actively remove the heat from the processer and take it far away, these kinds of innovative technologies should be used to increase the lifespan of the device,

but i guess a bigger block of metal achieves the same thing :slight_smile:

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With the new heatsink, a little shroulding made from aluminum flashing(thin sheet), and the VIM(x) mounted vertically, the chimney effect could be achieved.
I guess a new heatsink order is in order. :smile:

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I received the case after 6 weeks, then realized the extension board won’t fit in … sigh. KKSB please make a taller one can hold VIM3 + extension board!

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Heat pipes are doable, but it could make the heatsink block really big and fat. :smile:

The chimney effect is interesting, I’ve always wondered why heat dissipation is better this way. Unfortunately I am not smart enough to intuitively understand the Navier Stokes equations.

This got me really fascinated with the chimney effect at one point. https://en.wikipedia.org/wiki/Solar_updraft_tower

I wonder if there’s actually a real-life power plant functioning?

“The future is already here, it’s just not very evenly distributed.”

I’ve studied that in high school, believe me studying just stokes equation and Bernoulli’s principle is enough to make you believe you have a degree in Aerodynamics :rofl:, pretty tough though,

I see that heatpipes are a bit bulky, but what about vapor chambers, all one needs to do is slip one underneath an existing Khadas heatsink and better thermals are Assured, they are quite thin, like this one,

image

link to it

This are used in various devices like Razer laptops and some mobile phones for thinner and more powerful cooling.

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I feel the issue at hand is the way PCB Media Boxes have been made/designed call it what you like
They mostly run withing the range they are designed,
But
As I have seen in many many boxes, (i have a few too many) as much heat is seen on the under side of the PCB around CPU, then completely enclosed in a small plastic box with No vents,

A common joke between RDFKTV and my self, must cost lots to cut or mold vent/slots/space for air to circulate, sometimes they put Vents in the base, but the box is pretty enclosed except for Plug port.

As proven a slab of metal/heat sink on the bottom as well as top does help with cooling
Mount it sideways as hot air rises away, it draws in the around around it in and over CPU and area.

Then marketing take over and because things have to look peachy and appealing (eye candy)
Don’t want to ship box with to much air space large size costs etc
Make it small, tight and low profile… :hot_face:

Some cases this works, but in others it’s history

Seen the NEW Play Station 5 looks like a little chimney like :sunglasses: wonder if they thought abut it :slight_smile: :cold_face::upside_down_face:

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