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Serious Intel CPU bugs (2016)

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Re: Serious Intel CPU bugs (2016)

#21

Post by TrickyRick »

kuschku wrote: post #8
dataflow wrote: post #4

Out of curiosity, if you notice a CPU bug in a computer under warranty, is there anything the vendor is usually obligated do, or are they under no obligation to do anything about a CPU bug? Is that considered a defect they have to handle? (Edit: I'm assuming the USA, and I'm assuming bugs that were not known to the vendor at the time of the sale.)

Under EU law (this is not legal advice), any bug that wasn't known to you at time of sale, but was present at time of sale, has to be fixed by the vendor. For 2 years after sale usually, some countries have longer (afaik, Norway for example has it set at 5 years. As EEA member, they also follow the EU laws on warranty).

Good luck explaining to a random vendor what the problem is though. They also need to verify that the problem exists and most of them won't have a clue what you're talking about, they'll just turn the computer on and notice that it's working.

If you're a company buying from more qualified vendors then it might be a different story, however at that point consumer law does not apply to you.

Re: Serious Intel CPU bugs (2016)

#22

Post by philjohn »

chrisper wrote: post #9
kuschku wrote: post #7

Earlier quoted context omitted.

It looks like you'll see a significant slowdown, PostgreSQL with pgbench sees a 7% to 16% slowdown. https://www.postgresql.org/message-id/20180102222354.qikjmf7... Of course, this depends on workload — gaming will see different results than computationally heavy tasks. It is likely that games using Vulkan, DX12 or OoenGL's AZDO functions will see much lower performance impact (because they usually only do a handful o…

I am also quite annoyed because I paid premium (Intel) prices with the expectation to get premium speed. Now if I can just get the same performance cheaper with AMD, maybe I should just return the whole thing.

Which chip to get depends on your usecase.

If you absolutely need the best single core performance you can, Intel is the way forward.

If multicore performance is important (lots of multitasking, lots of heavy processes running) then one of the 8 core Ryzen 7's will be better, for cheaper.

Re: Serious Intel CPU bugs (2016)

#23

Post by philjohn »

aristidb wrote: post #20
chrisper wrote: post #5

So I recently bought an 8700k. I was wondering if I should rather return it and get AMD instead? Not sure how much the recent bugs will impact me performance wise.

The very article mentions at the bottom that AMD has its fair share of nasty bugs recently, too. If anything, I would expect AMD to spend even less effort on validation (because they are not flush with cash).

Or, because they're not flush with cash, they go for a simpler to verify design.

Remember, a lot of the Zen arch was developed by Jim Keller, who is the brains behind the Athlon 64.

Re: Serious Intel CPU bugs (2016)

#24

Post by MulliMulli »

aristidb wrote: post #20
chrisper wrote: post #5

So I recently bought an 8700k. I was wondering if I should rather return it and get AMD instead? Not sure how much the recent bugs will impact me performance wise.

The very article mentions at the bottom that AMD has its fair share of nasty bugs recently, too. If anything, I would expect AMD to spend even less effort on validation (because they are not flush with cash).

What bugs?

Re: Serious Intel CPU bugs (2016)

#25

Post by m_eiman »

mehrdadn wrote: post #15
ta_wh wrote: post #11

Earlier quoted context omitted.

See the three-year warranty here for boxed CPUs: https://www.intel.com/content/dam/support/us/en/documents/pr... Note the first bullet under "WHAT THIS LIMITED WARRANTY DOES NOT COVER": "design defects or errors in the Product (Errata). Contact Intel for information on characterized errata." Guess we're not covered on this one. EDIT: That being said, given the potential scope of this issue (years of affected CPUs, ma…

Thanks for posting this! It seems self-contradictory to me. How can Intel warrant that > the Product will substantially conform to Intel’s publicly available specifications while simultaneously disclaiming warranty for > design defects or errors in the Product (Errata) ? If an instruction does something different than what their specs say on occasion, do they take that to mean it's substantially conforming to their s…

What they're saying is that they'll replace your chip if it behaves differently from all the other chips of the same model, not if ALL the chips are broken by design.

Re: Serious Intel CPU bugs (2016)

#26

Post by aristidb »

MulliMulli wrote: post #24
aristidb wrote: post #20

Earlier quoted context omitted.

The very article mentions at the bottom that AMD has its fair share of nasty bugs recently, too. If anything, I would expect AMD to spend even less effort on validation (because they are not flush with cash).

What bugs?

The article spends 4 paragraphs on them. Just one example:

    Although AMD’s response in the forum was that these were isolated issues, phoronix was able to
    reproduce crashes by running a stress test that consists of compiling a number of open source
    programs. They report they were able to get 53 segfaults with one hour of attempted compilation.

Re: Serious Intel CPU bugs (2016)

#27

Post by baq »

slivym wrote: post #13

As a former Intel employee this aligns closely with my experience. I didn't work in validation (actually joined as part of Altera) but velocity is an absolute buzzword and the senior management's approach to complex challenges is sheer panic. Slips in schedules are not tolerated at all - so problems in validation are an existential threat, your project can easily just be canned. Also, because of the size of the compa…

not quite true regarding the focus - you aren't building a $50B+ company when you don't have focus, it's just that their core compentency isn't fashionable right now. they can't grow in the markets they're in because they either own them completely or were driven out, so they're trying different ones (pivoting, if that's applicable to mature companies).

Re: Serious Intel CPU bugs (2016)

#28

Post by soziawa »

TrickyRick wrote: post #21
kuschku wrote: post #8

Earlier quoted context omitted.

Under EU law (this is not legal advice), any bug that wasn't known to you at time of sale, but was present at time of sale, has to be fixed by the vendor. For 2 years after sale usually, some countries have longer (afaik, Norway for example has it set at 5 years. As EEA member, they also follow the EU laws on warranty).

Good luck explaining to a random vendor what the problem is though. They also need to verify that the problem exists and most of them won't have a clue what you're talking about, they'll just turn the computer on and notice that it's working. If you're a company buying from more qualified vendors then it might be a different story, however at that point consumer law does not apply to you.

Well depending on how this is turning out there will be benchmarks that show the chips performing slower than before. I've read that many chips will be getting 17% slower in the best case and up to 30% in the worst case. That could be enough to warrant a return of the product.

Re: Serious Intel CPU bugs (2016)

#29

Post by kuschku »

badsectoracula wrote: post #19
kuschku wrote: post #7

Earlier quoted context omitted.

It looks like you'll see a significant slowdown, PostgreSQL with pgbench sees a 7% to 16% slowdown. https://www.postgresql.org/message-id/20180102222354.qikjmf7... Of course, this depends on workload — gaming will see different results than computationally heavy tasks. It is likely that games using Vulkan, DX12 or OoenGL's AZDO functions will see much lower performance impact (because they usually only do a handful o…

> or even OpenGLs immediate mode (which does one syscall per emitted vertex, in worst case) Perhaps with drivers written in the 90s for hardware from the 90s. Any OpenGL implementation worth its salt will buffer those requests on the client side until they need to be observed. Indeed this was a big feature in the heyday of DirectX 9 where D3D programmers had to count the drawcalls whereas with OpenGL you have way mor…

That's why I said in absolute worst case scenario. I know that in the past I actually wrote some program in high school that did use that.

Nowadays, thanks to vulkan and AZDO with glMultiDrawElementsIndirect, you're right, of course — you might even use a single syscall per frame.

That's why I said, in absolute worst case.

Re: Serious Intel CPU bugs (2016)

#30

Post by amelius »

kuschku wrote: post #8
dataflow wrote: post #4

Out of curiosity, if you notice a CPU bug in a computer under warranty, is there anything the vendor is usually obligated do, or are they under no obligation to do anything about a CPU bug? Is that considered a defect they have to handle? (Edit: I'm assuming the USA, and I'm assuming bugs that were not known to the vendor at the time of the sale.)

Under EU law (this is not legal advice), any bug that wasn't known to you at time of sale, but was present at time of sale, has to be fixed by the vendor. For 2 years after sale usually, some countries have longer (afaik, Norway for example has it set at 5 years. As EEA member, they also follow the EU laws on warranty).

> Under EU law (this is not legal advice), any bug that wasn't known to you at time of sale, but was present at time of sale, has to be fixed by the vendor.

Is this true for software as well?

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