Help with heavy Gold top CPUs

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kernels

Well-known member
Joined
Apr 14, 2016
Messages
672
Location
Auckland, New Zealand
Hi there forum gurus,

Was hoping for a bit of advice about how to deal with the types of processors shown in the picture. They have the big and heavy integrated, plated heatsinks which I assume are Copper based ?

Thanks!

Big_Gold_Tops.jpg
 
I think Jon ,Anachronism, may be the one to help here as he refines a lot of this type of material so I’ll leave it to him to outline his process.
 
There's a few schools of thoughts on these Kernels.

The safest way to get all the gold is to take the tops off with a heatgun and run the lids in AR separately to the smashed up bases. That way you're sure you have everything from the solder. The lids aren't always copper based, some are Tungsten based and they don't always need to be completely dissolved to get all the gold. You just need to be sure that you've got all the solder dissolved.
 
Thanks Jon, I will proceed with the straightforward approach then, I hope these end up being worth the hassle of hours of dissolving.

Silversadddle1, yes, I have informed the person who sent these that they would be worth more selling as-is, but not much interest on his part. These are the last parts of a bunch of stuff sent in for recovery, silly me making about $4 per hour at this point. Lessons are expensive, good lessons are very expensive!
 
So I finished the recovery from the ceramic CPUs, bit of what I assume to be Lead Chloride that messed things up a bit, but nothing too major. Just very disappointed with the ultimate yield and my 20% of that yield ends up not even coming close to covering my time and chemicals.

They scratch up your glassware and consume a tremendous amount of acid, which then leads to a lot of acid waste. The yield per CPU is good, but I reckon I will hang on to all my ceramic CPUs and sell them off when the Gold price spikes up.

Very interested to hear your results and thoughts once you have finished processing those Geo.
 
I processed probably about the same amount as in Geo's picture, and only ended up with about 20g Au. Not bad to do for yourself, but this was a toll-refine, so the 4g I take was not really worth it.
 
While you may have lost a bit on the cost of chemicals and waste treatment, it wasn't a total loss as you still ended up with a few grams. The experience and knowledge gained is priceless!

Dave
 
I actually used a page out of Butchers playbook and decided to use the "kill two birds with one stone" method but I am not capturing the excess NO2. I believe that I can dissolve all of the base metal and reclaim the silver as cemented silver with just 1000ml's of sulfuric acid and five pounds of sodium nitrate. This is apposed to multiple courses of AR that would have taken at least three gallons of HCl and the same amount of nitrate with the pain of reclaiming the silver as silver chloride. I am actually at the midway point of the refine and it's working great.
 
The copper/tungsten heat spreaders are soldered on with silver alloy braze. They easily fall off when free of grease and stickers and the chip is allowed to soak in dilute nitric acid. You end up with gold foils from the lid, a clean tungsten plate, a ceramic cpu housing, kovar plated gold legs, a cpu die, gold bonding wires (if present), and a solution containing copper and silver nitrate. Remove the gold plated bottom lids if you are working with cpus that have them (P60/75/90, etc). For ceramic bottom lidded cpus simply fracture the bottom lid enough to allow the acid into the core/bonding wire area of the cpu (expose the core).

Once everything falls apart, pull the tungsten plates out and rinse them with fresh water.

Processing the housings, foils, and remaining parts is straight forward.

I have routinely run 75 pound batches of these with ease in less than 1 week at room tempersture from raw cpus to cast Au bars. With active heating the process can be completed in 2-3 days.

Heating/Sweating the spreaders off is a poor course to take. The tungsten/copper spreader takes a ton of heat to get off, plus they fracture quite often and even worse the Au foil and Ag braze will alloy into the copper of the primarily tungsten spreader and make the rest of the process very tiresome. Additionally, the heating further complicates the recovery of the legs, cpu dies/cores and bonding wires.

Follow my protocol and you will be able to completely reverse engineer the entire chip without damaging the tungsten spreader, insoluble internal parts, or making recovery of the precious metals any more complicated than it needs to be. My method works for any gold top cpu with a raised heat spreader. I sort them by similar make and process each make together.

Direct treament in AR either with or without crushing results in a mix of ceramic shards bonded to tungsten pieces with a silver chloride passvation layer. The AR routes also lead to yellow tungsten oxide, ring around the bucket, false positive stannous chloride tests, and tungsten coprecipitation with your gold powder. It is never wise to process tungsten containing scrap directly in AR unless it is unavoidable. Remove the tungsten first.

I have literally run thousands of pounds of these types of cpus in the last 5 years. My method is the most direct route to the precious metals. As an added bonus you get nice large 99+% purity tungsten plates as one of your by products.

I hope this helps. You will likely see new youtube videos on this process after I post this. Remember you read it here first.

I have photos of these processes, but they are scattered across several cameras, sd cards, smart phones, and computers. I can try to locate some if any is interested in seeing chemically diseceted "gold topped" cpus (ones with integrated tungsten heat spreaders).

Steve
 
https://www.youtube.com/watch?v=tQ_R8Gr26kk
https://www.youtube.com/watch?v=Hv4CcaTVJqY
 
samuel-a said:
https://www.youtube.com/watch?v=tQ_R8Gr26kk
https://www.youtube.com/watch?v=Hv4CcaTVJqY

In that video you conveniently do not show how to remove the heavy integrated heatsinks. You say to remove it with heat, but I can assure you it takes forever to remove them with a MAPP gas torch.
 
Just smash it.
If it breaks, it's Tungsten and can go to AR with the ceramic. If it doesn't break it is copper.
Don't bother with heating it as the solder will soften at 600+ C.
 
samuel-a said:
Just smash it.
If it breaks, it's Tungsten and can go to AR with the ceramic. If it doesn't break it is copper.
Don't bother with heating it as the solder will soften at 600+ C.

Awesome, thanks for the reply, that is good info. I never imagined that Tungsten would break.
 
If you follow Sam's protocol you will be hard pressed to recover all of the silver and you will be picking tungsten shards out of the left overs if you want to sell it for an additional profit

Tungsten dissolved in AR also gives false positives to the stannous chloride test. As an added issue the tungsten will leave a yellow layer in your beakers and buckets. The yellow tungsten oxide can be removed, but it is just one more step you will need to perform to keep your reaction containers free of contaminates.

Steve
 
kernels said:
Hi there forum gurus,

Was hoping for a bit of advice about how to deal with the types of processors shown in the picture. They have the big and heavy integrated, plated heatsinks which I assume are Copper based ?

Thanks!

Big_Gold_Tops.jpg

Hi I would like to share my experience with these CPUs:

from AMD K5 gold top/ gold lid 10 CPUs 378g 2.45g Au or 6.48g Au/kg https://youtu.be/eJwodZri9qM
from 10 IBM 686 & 10 Cyrix 686 CPUs mix 830g 2.45g Au or 2.95g Au/kg https://youtu.be/irMDfWA5SM8

plus

from 4.96kg i386 & i486 ceramic CPUs mix 43g Au or 8.67g Au/kg https://www.youtube.com/playlist?list=PLLm8aBXzLPMM_NHr8UxLkDfOgApABQrzO
from 1,028kg AMD 486 5.9g Au or 5.73g Au/kg https://youtu.be/xHJ7RoglI_0
from 10 AMD 386 162g 1.57g Au or 9.69g Au/kg https://youtu.be/DLAmanHvUxM

also, I've noticed something peculiar:
about 0.046g Au per gram of kovar lids (I've got almost the same yield from all kovar lids processed so far, regardless of the manufacturer)
another observation I've made (when it comes to ceramic CPUs with gold plated kovar lid only) is the corelation between the yield form the lid and the overall yield of a CPU (38-40% of the gold is in the lid)

maybe it's all just a coincidence but I still find it strange...
 

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