News AMD Recycles Dual-Chiplet Ryzen 7000's as Ryzen 5 7600X CPUs

Apr 1, 2020
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The only newsworthy thing about this is that AMD seems to have learned their lesson and kept the operational chips on the same CCD instead of a 2+2 or 3+3 arrangement the way they did in the past where the cores were on different CCDs and would incur a performance penalty.
 

escksu

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Makes me wonder if the same system will allow them to make a saleable unit out of two partially damaged chiplets.

Yes of course. But there will be some added latency due to location of the cores. However, if AMD did not fuse off the L3 cache, you will get 2x the cache.

It's commonly done in epyc.
 
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cfbcfb

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I read AMD's answer on why it has two, and I did it three times. It still makes no sense.

I can't imagine a company intentionally putting two on the die and turning one off unless the process of putting each one on has a high failure rate, and they just write it off as a lower core count product and sell it anyhow?

What actually happened is that it doesn't cost much if anything to use two on a die than one, since their manufacturing cost was revealed to be about $70? So they fuse one ccd on a batch if they sell more one ccd cpu's than they intentionally made that way.
 
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escksu

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I read AMD's answer on why it has two, and I did it three times. It still makes no sense.

I can't imagine a company intentionally putting two on the die and turning one off unless the process of putting each one on has a high failure rate, and they just write it off as a lower core count product and sell it anyhow?

What actually happened is that it doesn't cost much if anything to use two on a die than one, since their manufacturing cost was revealed to be about $70? So they fuse one ccd on a batch if they sell more one ccd cpu's than they intentionally made that way.

It makes perfect sense actually. Its to meet demands and reduce time needed for testing.

No, it doesn't cost them anything actually and they could potentially make more money. For CPUs that has 2 perfect dies, AMD simply mark it as 7950, if not so good, 7900.... If 1 die is very bad, 7700/7600 then. AMD/Intel usually do not rework CPU if it fails test. Imagine they solder jsut 1 die onto the substrate and found it to be bad, the whole CPU is useless... Now, they have 2 dies, if 1 is bad, they can still use it. Reduce wastage.

Of course, having 2 dies instead of 1 on each CPU means that the number of CPUs you can make is potentially halved..... So, it depends on demand. Right now, I believe AMD already know that 7950/7900 has very high demand. 7700/7600 will not have such demand at least till B650 boards are out.
 
Of course, having 2 dies instead of 1 on each CPU means that the number of CPUs you can make is potentially halved.....
No, because the space on the wafer is still the same, you only get more yield because each die is smaller so more of them will be fine.
Having multiple dies is just easier and more importantly cheaper.
 

jp7189

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Wait.. are you all saying that every 7000 series ships with 2 CCDs? There are none produced with a single CCD?

The way I understood the article is most 7600/7700 ship with 1 CCD, but occasionally there would be a 2 CCD package with 1 fused off due to failure post packaging.
 

cfbcfb

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It makes perfect sense actually. Its to meet demands and reduce time needed for testing.

No, it doesn't cost them anything actually and they could potentially make more money. For CPUs that has 2 perfect dies, AMD simply mark it as 7950, if not so good, 7900.... If 1 die is very bad, 7700/7600 then. AMD/Intel usually do not rework CPU if it fails test. Imagine they solder jsut 1 die onto the substrate and found it to be bad, the whole CPU is useless... Now, they have 2 dies, if 1 is bad, they can still use it. Reduce wastage.

Of course, having 2 dies instead of 1 on each CPU means that the number of CPUs you can make is potentially halved..... So, it depends on demand. Right now, I believe AMD already know that 7950/7900 has very high demand. 7700/7600 will not have such demand at least till B650 boards are out.

You have the same malady as the guy from AMD has. Not all of the 7600's have two CCD's. Only some of them. So they did exactly what I said. Turned one of them off to produce more low end chips.

I was in semi manufacturing. If you get to the point where you've tested a component before attaching it to a die (and of course, you should) and it's okay, but not after its mounted, you missed your earlier screwup. If you're damaging components just by putting them on a die, then your manufacturing stinks.

But as usual, it's as simple as what I just said. They made more 7950's than they can sell, and many are buying lower end.
 

kjfatl

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Somewhere in the packaging process an error occurred. One die did not work after assembly.
So do you throw it away or fuse the connection to the bad die and sell it as a 6 or 8 core model?
Of course you sell it!
Duh!!
Bubba ain't no idiot.
It is quite possible that the processor yield is so high that AMD is not testing, or only minimally testing the CPU dies before assembly. Testing is not a free process. If so, this would be very goon news for AMD. If 5% of the CPU dies fail, fuses are set and the ones with a single bad CPU are simply marked as the lower performance part.