Klondike heatsink sourcing

[SebastianJu]

I searched a bit now and saw this wholesale website that has quite a lot heatsinks for often very low prices... if we need enough parts thats probably possible. And i think if a company has a minimum of 1000 and you call them saying you only can take 500 im sure they will bite anyway.

For now i only searched for the german word of heatsink "kühlkörper" and added 100mm. Its astonishing how many companies are popping up that create such things for low.
For example this product: http://german.alibaba.com/product-gs/aluminum-heat-sinks-97-w-x60-h-100-l-mm-712256516.html
Though not very much cheaper. Or this: http://german.alibaba.com/product-gs/-font-b-100mm-b-font-1200mm-width-aluminum-extrusion-welded-led-heatsink-for-machine-power-server-electronic-computer-led-pcb-amplifier-581032609.html
The price seems very low for minimum 100mm. But a call cant be wrong.

Or try this search: http://german.alibaba.com/product-list/k%25C3%25BChlk%25C3%25B6rper_100mm/--radiator%2Bbox%2B100mm.html

You can click the companies name too in the list, there are many companies in this business it seems. You can find even more companies with taking away the 100mm.

Its probably best to check out the prices with one or more of these companies.

[sensei]

The heatsink (1 per K16) would mount with 4 fasteners, placed in the middle of each 4 groupings of ASICs. These are not the same as the holes for the standoffs which are at each corner.

[SebastianJu]

The heatsink (1 per K16) would mount with 4 fasteners, placed in the middle of each 4 groupings of ASICs. These are not the same as the holes for the standoffs which are at each corner.

Now i see what you mean... the purple dots are the holes in the picture of klondike first post. But the whole board is 10x10cm... thats 100x100mm if im not mistaken. So all 8 holes will be covered with a heatsink of 100x100mm anyway. Or if you want to use the 4 outer holes to mount the board to a case or so, then this would mean you first have to mount the board to the case, then the heatsink, so that heatsink and board arent a unit first. But that cant be because the heatsink needs cooling paste... am i have a wrong thought?

[TomKeddie]

The heatsink (1 per K16) would mount with 4 fasteners, placed in the middle of each 4 groupings of ASICs. These are not the same as the holes for the standoffs which are at each corner.

Which gives me an idea, there is no reason to concentrate the heat pads on the heatsink behind the ASICs.  It might be easier to cover the entire heatsink with heat pad and draw the heat away from the entire board instead of just the regions with ASICs.

[SebastianJu]

The heatsink (1 per K16) would mount with 4 fasteners, placed in the middle of each 4 groupings of ASICs. These are not the same as the holes for the standoffs which are at each corner.

Which gives me an idea, there is no reason to concentrate the heat pads on the heatsink behind the ASICs.  It might be easier to cover the entire heatsink with heat pad and draw the heat away from the entire board instead of just the regions with ASICs.

Ah, now i get it. Heat pads are the vias bkkcoins mentioned. But i believe it wouldnt help much because the vias need contact to the to be cooled unit. The pcb itself is a bad heat conductor. So i doubt that a via that is a cm beneat an asic can take away much heat. And it might be that the vias cost something?

Whats the status here? Since 2 days no new posts? Were the links to the manufacturers in china usefull(-less)?

[sensei]

bkkcoins is suggesting a heatsink of dimensions 90x80mm. You cannot cover the standoff/mounting holes or the thru holes for the PCIe connector (power).

[SebastianJu]

bkkcoins is suggesting a heatsink of dimensions 90x80mm. You cannot cover the standoff/mounting holes or the thru holes for the PCIe connector (power).

As far as i read at alibaba.com the companies creating heatsinks often calculate in tons, so the weight... that means a smaller heatsink most probably will mean less cost too then.
Plus i didnt understand how to mount the whole unit then into a rack when the heatsink is above the mounting holes at the border. Then the unit has to be mounted together and the heatsink is holding the unit then.

[t13hydra]

I am speaking with manufacturers to have heatsinks made for the Klondike board. Having heatsinks made is going to be less expensive than purchasing and modifying any current solution. I need to know who is planning on purchasing boards, what quantity, and whether or not they would want a heatsink.

Specs are:
100x100x25mm
3mm base
1mm fins
2mm spacing
6000 series aluminum
4 mounting holes drilled, located in center of each 4 chip group.
Flat base/underside

This is a one time deal. Enough heatsinks need to be purchased to cover all the boards, with a few extra. Purchasing additional heatsinks in low quantity will be prohibitively expensive. These heatsinks will not be made available to the general public. They will only be made available to those offering bulk purchasing as I cannot sell these piecemeal. I will be offering them as part of a package to those who purchase chips through me.

Group buy coordinators, Large private buyers, and Klondike resellers need to contact me ASAP.

I would also like a quote for this for 100 and 500 pieces. I already have my supplierz but want to verify what he has given me. So far good prices, but i wonder if it's possible to be even cheaper than him.

Thanks,
Steve

[ryepdx]

Interested in getting some quantity between 100 and 500. I'll get you a hard number as soon as I have one...

[steamboat]

questions, comments, concerns?

[desert_beagle]

OK this is what I would do.  So from Avalon website the dimensions of the chips are 7 mm x 7 mm so I would opt out for individual heatsinks like this one http://www.newegg.com/Product/Product.aspx?Item=N82E16835708011 or http://www.newegg.com/Product/Product.aspx?Item=N82E16835708012.  The first one is 6.5mm and the latter is 10mm.  They are designed to cool video car memory so I think they would be suitable for avalon chips.

[steamboat]

OK this is what I would do.  So from Avalon website the dimensions of the chips are 7 mm x 7 mm so I would opt out for individual heatsinks like this one http://www.newegg.com/Product/Product.aspx?Item=N82E16835708011 or http://www.newegg.com/Product/Product.aspx?Item=N82E16835708012.  The first one is 6.5mm and the latter is 10mm.  They are designed to cool video car memory so I think they would be suitable for avalon chips.

This approach has been discussed before. They are not as efficient at dissipating heat, cannot be secured well, and are insanely expensive.

[Bicknellski]

OK this is what I would do.  So from Avalon website the dimensions of the chips are 7 mm x 7 mm so I would opt out for individual heatsinks like this one http://www.newegg.com/Product/Product.aspx?Item=N82E16835708011 or http://www.newegg.com/Product/Product.aspx?Item=N82E16835708012.  The first one is 6.5mm and the latter is 10mm.  They are designed to cool video car memory so I think they would be suitable for avalon chips.

How many fans can be powered? Check the board design... looks like a single 3 pin for 1 fan right? So doing that might not be ideal. I agree with the 1 larger heat sink properly mounted will give you the maximum heat dissipation. Raised or not let us see what BKKCOins comes up with in his tests. I will be sending him 4 heat sinks for testing. Ignore the oversized heat sinks I am shipping as BKKCOINS will mod them to suit his plan but you can use the dimension and spacing for the fins to give you an idea when his test results come out.

https://109.201.133.65/index.php?topic=210635.msg2223916#msg2223916

He will mod them how he thinks and give us all feedback. I am loving the CNC idea and I hope that won't  add too much to my costs here in Indonesia if your design is best steamboart. Fans need some sort of attach point right? Top down blowing directly like a CPU?

[SebastianJu]

So from Avalon website the dimensions of the chips are 7 mm x 7 mm

Can you give me a link? Im in the process to find out what packaging i need to spread the asics to buyers. Till now i thought the chips will come on a roll but burnin now said he thinks they will come in tubes. I need to know this in order to order the needed packaging...

[alfabitcoin]

So from Avalon website the dimensions of the chips are 7 mm x 7 mm

Can you give me a link? Im in the process to find out what packaging i need to spread the asics to buyers. Till now i thought the chips will come on a roll but burnin now said he thinks they will come in tubes. I need to know this in order to order the needed packaging...

Sebastian, go to github avalon release, there is chip packaging and dimensions.

[SebastianJu]

So from Avalon website the dimensions of the chips are 7 mm x 7 mm

Can you give me a link? Im in the process to find out what packaging i need to spread the asics to buyers. Till now i thought the chips will come on a roll but burnin now said he thinks they will come in tubes. I need to know this in order to order the needed packaging...

Sebastian, go to github avalon release, there is chip packaging and dimensions.

Thanks... i thought that is only for building it... i now found the pdf (https://github.com/BitSyncom/avalon-ref/tree/master/PDF) with the measures of the chips... unfortunately i dont find info about how the chips are shipped... in which form. So that i know what packaging i have to buy.

[ecliptic]

questions, comments, concerns?

Looks like a good design.  Are you planning on using a thermal pad between the extruded squares and the exposed copper on the back of the PCB or have them contact it directly (maybe with a little bit of thermal paste)?

With that design will you use something on/with the screws for mechanical support to help keep the heatsink in thermal contact with the pads?  Perhaps like an aluminum standoff or insert from McMaster carr, or extrude aluminum there and tap a hole?  Are the holes threaded already?

[steamboat]

questions, comments, concerns?

Looks like a good design.  Are you planning on using a thermal pad between the extruded squares and the exposed copper on the back of the PCB or have them contact it directly (maybe with a little bit of thermal paste)?

With that design will you use something on/with the screws for mechanical support to help keep the heatsink in thermal contact with the pads?  Perhaps like an aluminum standoff or insert from McMaster carr, or extrude aluminum there and tap a hole?  Are the holes threaded already?

BkkCoins pointed some things out in his thread so the design is changing to flat, with CNC'd recesses for the PCIE thru-hole connection. This design would have connected directly to the copper w/ paste.

The holes in the center of each group of chips are tapped for a m3 screw. W/ or w/out a spring is TBD.

[ryepdx]

Steamboat, do you have any plans to also provide heatsinks for the Nano?

[bitcoiner49er]

Whatever size ends up being chosen, I would think we will want standoffs/spacers to prevent the PCB from curving/warping and loosing contact in the middle due to potential over tightening on the 4 corners. They can be measured to make sure the heat sink still has an interference fit, but keep the warp-age to a minimum. (Think Phat Xbox PCB's   )

Hmm, just saw the CAD pic for the K16 today. Good design, renders my above concerns mostly obsolete.