"KalmX AMD Edition" - RADEON RX 6400 Passive Cooling Mod

robbee

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i dont know how to attach the copper heatsink to the CNC copper plate. I found a thermal adhesive on amazon. https://amzn.eu/d/037UTEx4
is it able to do the job?.
Also do i have to replace the termal pads for better performance?

Low temp solder paste. There are mixtures of Tin and Bismut that melt at about 140 degrees. There are also some silver infused mixtures that melt at about 180-190 degrees with better heat conductivity, but that shouldn't be required if there is a lot of surface being soldered together.
 

FlexxRocket

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can i bake it in my oven or is it so toxic that you have to get a seperate oven just for this process?
sorry for these questions i am new to this
 

robbee

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can i bake it in my oven or is it so toxic that you have to get a seperate oven just for this process?
sorry for these questions i am new to this

I wouldn’t advice it. A kitchen oven is good enough as you don’t need very exact temperature control, but I wouldn’t cook in it after you’ve used it for soldering.
 
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FlexxRocket

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The copper Platte Just arrived!
In the 3d file the holes were 2mm in diameter
So i would Drill the holes to 2.1 mm and cut the Threads with the M 2.5 thread Cutter
This is How you did this also ? @REVOCCASES

 

robbee

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If you don't have cutting oil, high fat milk works well too with copper. Make sure the tap doesn't tilt when you're cutting. This works best if you put the tap in a drill press and then spin it manually with your hands.
 

FlexxRocket

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@REVOCCASES what thickness are your thermal Pads? Because i think 0.5 mm is too much .
The gap between Cooper plate and Chip is too big i think ( when using 0.5mm pads)
Are these pads neccesery?
 
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REVOCCASES

Shrink Ray Wielder
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@REVOCCASES what thickness are your thermal Pads? Because i think 0.5 mm is too much .
The gap between Cooper plate and Chip is too big i think ( when using 0.5mm pads)
Are these pads neccesery?

Sorry, my picture is misleading. I noticed the same like you and ended up using paste on the memory, just missed to update my post. The gap between GPU die and memory is very small, maybe just 0.1mm.
 
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FlexxRocket

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One Last question :
I am a beginner to Solder paste :
My idea was to put this solder paste:
On top of the copper plate like this:And then putting it With the copper heatsink in the pre heated Pizza oven at 140 degree celcius for about 5min(?)
Do you think that would work?
Thanks in advance
( of course i will remove the card before putting it in the oven)
 

REVOCCASES

Shrink Ray Wielder
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One Last question :
I am a beginner to Solder paste :
My idea was to put this solder paste:
On top of the copper plate like this:And then putting it With the copper heatsink in the pre heated Pizza oven at 140 degree celcius for about 5min(?)
Do you think that would work?
Thanks in advance
( of course i will remove the card before putting it in the oven)

the paste look good...

no need to spread it, just apply some circles or lines but not use toooo much... leave some distance from the threads, e.g.:

20230421_093949.jpg

after applying the paste, you should clamp / fix the two parts somhow, else they'll move during soldering... e.g. use some metal clips:

20230414_154723.jpg

since you don't have any heatpipes, you can just set the oven to max., also no need to preheat, the small pizza-ovens will get hot fast enough.

observe the parts and when you see some silverish shiny solder come out of the gap between the parts, you can turn off the oven. let the parts cool down inside the oven with the door open... done!
 

FlexxRocket

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How do i prevent the paste going into the threads?
2 of the 4 Threads are Outside of the heatsink ( See the pictures) and two are directly under the heatsink .
 

REVOCCASES

Shrink Ray Wielder
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How do i prevent the paste going into the threads?
2 of the 4 Threads are Outside of the heatsink ( See the pictures) and two are directly under the heatsink .
Like I said above, keep some distance from the thread holes and don't use too much paste.

I'd place the small copper plate above the heatsink during soldering. For safety you can also screw in those two screws during soldering.