Question So, Intel DOES "die harvest" after all... according to AT front-page article.

Aug 25, 2001
42,745
315
126
#1
https://www.anandtech.com/show/13660/amd-athlon-200ge-vs-intel-pentium-gold-g5400-review/

* Intel harvests both 2+2 and 4+2 dies to make G5400 parts. It's impossible to know which one you have without removing the lid and measuring the die area.

Right under and in the comparison chart. Intel Pentium Gold 5400, it says is made from both 2-core, as well as 4-core dies (harvested).

I've personally speculated that Intel has been doing this for years, but the Intel fans on this forum all poo-pooed the idea, and claimed that Intel's yields "were so high that they didn't need to 'harvest'", and that "Intel's brand would be damaged, should consumers ever find out that they 'harvest'".

Well, finally, it's in writing, on AT's front page no less in an article.

So, Intel fans on this board, EAT CROW.

Edit: Honestly, it just makes good business sense to me. Done properly (secretly?), it shouldn't damage the brand at all. But it would be interesting, if truth-in-labeling laws apply to CPUs in that way, such that the packaging of those CPUs in retail, would be required to carry a sticker, "Intel B-stock".
 

whm1974

Diamond Member
Jul 24, 2016
6,312
243
96
#2
From reading that article I don't there there is any real difference with the two, aside from TDP.
 

BigDaveX

Senior member
Jun 12, 2014
321
35
101
#3
Intel has been doing this kind of thing since the Core 2 era, if not even earlier. It shouldn't come as a surprise to anyone that they don't throw away usable dies if they can be made to function as something lower-end.
 

Spartak

Senior member
Jul 4, 2015
287
131
86
#4
Yeah not sure why this is a surprise to anyone. Also, for a textbook harvested chip we already had the 8086K last year.

Scrap that, still early. Confused binning with harvesting (and assumed this was about the i9-9990XE).
 

NTMBK

Diamond Member
Nov 14, 2011
8,177
150
126
#5
"EAT CROW"? Chill out, Larry :) It's just computer parts, no need to take it so seriously.
 
Feb 23, 2017
449
329
96
#6
I agree fully with the edit; makes sense it increase the effective yield by harvesting defective dies. I'm not sure how much scope there is for harvesting in low core count dies though.
 

Insert_Nickname

Diamond Member
May 6, 2012
3,440
88
126
#7
I thought this was more-or-less an open secret. I mean, why wouldn't they use a quad core die with perhaps only a defective core? There shouldn't be any difference at all in functionality between quad and dual core dies from the same generation.

Better to get -some- return, then just toss it in the bin. I'm more surprised we haven't seen tri cores from Intel, like AMD did. A 3C/6T product with the right specs and pricing could be attractive. Or could have been is perhaps more appropriate given today's market.

I agree fully with the edit; makes sense it increase the effective yield by harvesting defective dies. I'm not sure how much scope there is for harvesting in low core count dies though.
If there is only 2 cores, then yeah, that's going to be a problem. No single core* CPUs anymore, and good riddance to that.

On the other hand, with such a small die, yields should be excellent.

*The Celeron G470 was the last of the line. SB single core with HT.
 
Mar 10, 2004
28,286
180
126
#8
How could AMD or Intel afford to waste a die that could be saved and sold?
 

DigDog

Diamond Member
Jun 3, 2011
9,999
110
126
#9
WHY would AMD or Intel afford to waste a die that could be saved and sold.

There is no downside to you, consumer, if your 2-core CPU has 2 more, disabled cores on it. Why the worry?

Besides, brand reputation is established at the high end, far more than the budget end - that's why garbage like Renault races F1.
 

bononos

Diamond Member
Aug 21, 2011
3,617
3
91
#10
Would harvested
https://www.anandtech.com/show/13660/amd-athlon-200ge-vs-intel-pentium-gold-g5400-review/

....................
Edit: Honestly, it just makes good business sense to me. Done properly (secretly?), it shouldn't damage the brand at all. But it would be interesting, if truth-in-labeling laws apply to CPUs in that way, such that the packaging of those CPUs in retail, would be required to carry a sticker, "Intel B-stock".
Would there be a performance hit from harvested dies for the 2core/4 thread models?
 

BigDaveX

Senior member
Jun 12, 2014
321
35
101
#13
I don't know how intel does inter-core communication on that die, but there could be extra latency on the 4+2 vs 2+2 from extra hops the data needs to traverse.
Presumably they just disconnect the non-functional cores from the ring bus, leaving the two remaining cores communicating directly. And even if it had to poll the inactive cores, the latency penalty would most likely be extremely minimal.
 

Mopetar

Diamond Member
Jan 31, 2011
4,396
339
126
#14
Does it really matter if they do or not? As long as the product you get still functions within specifications, I don't see any problem.

Has anyone tried to see if it's possible to unlock any extra cores (if they're functional) if you get the 4-core version like you might be able to do with the X3 Athlon / Phenom chips?
 
Dec 10, 2018
63
109
51
#15
Presumably they just disconnect the non-functional cores from the ring bus, leaving the two remaining cores communicating directly. And even if it had to poll the inactive cores, the latency penalty would most likely be extremely minimal.
That makes sense, but I still have questions... Is there any more information on how the ring bus works internally?

The ring bus is fully pipelined and so I would expect there to be something like registers at each node on the bus (or even in between). So even with a core disabled, there is would still be the extra "hop". I do agree with you that it'd be minimal regardless because they're so close together anyways.
 

BigDaveX

Senior member
Jun 12, 2014
321
35
101
#16
Has anyone tried to see if it's possible to unlock any extra cores (if they're functional) if you get the 4-core version like you might be able to do with the X3 Athlon / Phenom chips?
As far as I know, that's never been possible on Intel chips. And I don't think it's even been possible on any AMD chips since Bulldozer.

That makes sense, but I still have questions... Is there any more information on how the ring bus works internally?

The ring bus is fully pipelined and so I would expect there to be something like registers at each node on the bus (or even in between). So even with a core disabled, there is would still be the extra "hop". I do agree with you that it'd be minimal regardless because they're so close together anyways.
From a quick glance over articles relating to Sandy Bridge (where they first introduced the ring bus), it sounds like the bus is wired in parallel rather than in series, so presumably in instances where one or two cores aren't working they just cut the physical connection to the bus and put something to the effect of "cores at Ports A and B, ignore Ports C and D, they don't exist" in the chip's microcode. Admittedly, however, that's entirely my speculation.
 
Dec 10, 2018
63
109
51
#18
As far as I know, that's never been possible on Intel chips. And I don't think it's even been possible on any AMD chips since Bulldozer.


From a quick glance over articles relating to Sandy Bridge (where they first introduced the ring bus), it sounds like the bus is wired in parallel rather than in series, so presumably in instances where one or two cores aren't working they just cut the physical connection to the bus and put something to the effect of "cores at Ports A and B, ignore Ports C and D, they don't exist" in the chip's microcode. Admittedly, however, that's entirely my speculation.
I'm speculating just as much as you are ¯\_(ツ)_/¯
 

Topweasel

Diamond Member
Oct 19, 2000
4,638
295
136
#19
https://www.anandtech.com/show/13660/amd-athlon-200ge-vs-intel-pentium-gold-g5400-review/




Right under and in the comparison chart. Intel Pentium Gold 5400, it says is made from both 2-core, as well as 4-core dies (harvested).

I've personally speculated that Intel has been doing this for years, but the Intel fans on this forum all poo-pooed the idea, and claimed that Intel's yields "were so high that they didn't need to 'harvest'", and that "Intel's brand would be damaged, should consumers ever find out that they 'harvest'".

Well, finally, it's in writing, on AT's front page no less in an article.

So, Intel fans on this board, EAT CROW.

Edit: Honestly, it just makes good business sense to me. Done properly (secretly?), it shouldn't damage the brand at all. But it would be interesting, if truth-in-labeling laws apply to CPUs in that way, such that the packaging of those CPUs in retail, would be required to carry a sticker, "Intel B-stock".
VL it comes from AMD's time with the Phenom X3 and stuff.

Intel made this proclamation that they would never sell CPU's that failed tests in anyway. They were still reeling from the Pentium MMX and PIII 1.13GHz recalls (the later was supposedly only 100+ chips shipped mostly to reviewers).

But the truth is somewhere between AMD's binning and no binning at all. Shortly after the PIII coppermine release Intel changed up how they handled their fabs. They instituted processes for making sure all fabs being identical. No more shunning Malaysian serial numbers and hunting Costa Ricain serial number in OEM chip bins. Anyways by the time Intel had made that statement they were comfortable with their manufacturing and being able to make 100's of millions of chips a year helped with that, that they could pre-bin their wafers right away. After the pre-binning they could do the normal tests and bin for speed. That meant they would lazer off cache or cores well before actually figuring out if it was bad making so it never failed.

That said even that is long gone. On the server side Intel has three dies that they sell from 4-10 cores, 12-18 cores, 20-28 cores. None of them make sense without binning and no way Intel could risk throwing away a useable die on 28 core production line. Every chip on that line is thoroughly tested to make sure they can find the highest sku they can sell each die to maximize margin. They might be more willing then ever before to throw away 4c and 2c dies. But the days of them just pre-binning before testing is long gone on the chips that matter the most.
 
Oct 9, 1999
11,244
40
126
#20
Why do we care if a company harvests chips?
Objective people do not care.

Larry is right about one thing though the intel fanboys rabidly denied that intel harvested chips for the past several decades.
 
Mar 10, 2006
11,709
102
126
#21
Objective people do not care.

Larry is right about one thing though the intel fanboys rabidly denied that intel harvested chips for the past several decades.
Proof? Seems like a straw man. Intel literally disables parts/features on chips all of the time. Look at the Xeon lineup or even something like 9700K which has cache disabled. Even the 9600K literally has two cores disabled.
 
Mar 10, 2004
28,286
180
126
#22
It may be that Intel, for a time, stayed away from using defective dies due to the problems that occurred, but then went back to the practice as things improved.

I always thought that prior to six core and up dies, there was basically a single 4 core die that was made into all of the chip variants - 2C/2T, 2C/4T, 4C/4T, and 4C/8T.
 

BigDaveX

Senior member
Jun 12, 2014
321
35
101
#24
Proof? Seems like a straw man. Intel literally disables parts/features on chips all of the time. Look at the Xeon lineup or even something like 9700K which has cache disabled. Even the 9600K literally has two cores disabled.
Heck, if you really want to go back, Intel has been disabling major components of their chips since at least around 1990, when they sold 486DXs with defective floating-point units as 486SXs.
 

jpiniero

Diamond Member
Oct 1, 2010
5,996
126
126
#25
It's rare for Intel to disable cores on desktop, but might just be a part of the shortage issue. I would expect this to be commonplace going forward however.

Proof? Seems like a straw man. Intel literally disables parts/features on chips all of the time. Look at the Xeon lineup or even something like 9700K which has cache disabled. Even the 9600K literally has two cores disabled.
You think they don't have a native 6 core die? I would be surprised.
 


ASK THE COMMUNITY

TRENDING THREADS