Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

It was never advertised, and Intel very specifically said AVX-512 instructions will not be available. Some motherboard manufacturers made them available anyway, now Intel is fixing that.

It's like buying a car with an advertised speed limiter of 155mph, then finding that actually it can go 170mph, and then the manufacturer fixes the speed limiter with a software update. Yes we know the car could go faster, but the speed limited version is the one that was actually advertised.



Not sure how others do it, but I don't only buy products based on advertisements, but rather by the actual properties the product has.

But it's not like this changes anything legally. Products get worse due to software changes all the time (especially through cloud services shutting down) and as far as I know there haven't been any successful lawsuits about it.


> now Intel is fixing that

That's not a fix. That's a disabling. A fix repairs something.


If AVX-512 was not in scope yet left turned on, parts may operate outside design limits, there's system-level validation that may not have been run, and specs that are at risk. Think about the scale of all PC OEMs that use these CPUs, rather than a specific product.

For example, it's known that AVX-512 is power hungry and significantly increases TDP (heat). Do all Alder Lake based products have the thermal headroom? If CPUs operate outside of the envelope communicated by Intel, they may not be entirely stable, and parts could fail earlier than expected.


Bringing a product in line with specification is very much fixing it. Even if the fix happens to be disabling something.


There was no specification about this feature until immediately prior to launch.

When a company announces with years in advance a new product (e.g. Alder Lake), that is the replacement for their previous product (i.e. Rocket Lake & Tiger Lake) and in that series of products the most valuable feature is backward software compatibility and the new product will no longer have this feature, one would expect that the company should publicize vigorously the fact that the replacement product will not match the features of the replaced products.


Sure, but that's a customer expectation vs legal obligation.

Like, my sister bought the new M1 MacBook Air, only to discover that it doesn't support dual external screens - while her previous Air did. So there was absolutely an expectation there that any new MacBook Air would also support dual screens, right?

But, at the end of the day - it is mentioned in the spec sheet. She could have checked. Just assuming that a feature is there is not enough. What's more - if dual screens worked originally, and then they stopped working after an update - that wouldn't be a bait and switch either, it would be a fix to bring the computer back in line with its spec.

And yes, I agree that it would suck.


The difference is dual screens don't work on the M1 MBA because it physically only has two display controllers in the silicon, one of them wired to the internal panel, and the other muxed to the two TB ports. The M1 Pro has two external display controllers, and the M1 Max four. I can show you where they are on the die shots, and that it's not artificial crippling.

But what Intel is doing here is disabling existing silicon that exists and works.


Sure, but as a customer that's irrelevant, right? You had a MacBook Air, used it with two displays, then you buy a new MacBook Air and bam, it doesn't work with two displays. The technical nitty gritty is not really relevant - at least the comment I was replying to sounded this way. That what the customer expects is more important than what is on the spec sheet? The fact that previous Intel CPU supported AVX-512, and the new one doesn't - so whether this fact is or isn't mentioned in the spec sheet is not important, because what the customer expects should be ultimately what decides what is "ok".


Yes, but once it has shipped and people may have come to depend on it it will break stuff, not fix stuff.

Besides the obvious benefit of first having benchmarks out there claiming these chips are better than they really are. So this change just benefits Intel, and nobody else. If it would be a fix then it would be that something that was advertised did not work, and now it does.


>>Yes, but once it has shipped and people may have come to depend on it it will break stuff, not fix stuff.

If people depend on functionality that is explicitly unsupported then I don't know what to say other than that I don't see how that's Intel's responsibility. If you buy a CPU that doesn't support AVX-512 instructions in order to use AVX-512 instructions then ...I think you're the one who is wrong here.

To go back to my car analogy - if you buy a car that isn't type approved for towing, and yet you install a tow bar anyway, you can't complain to the manufacturer if stuff breaks.

>>Besides the obvious benefit of first having benchmarks out there claiming these chips are better than they really are

Are any of the published benchmarks using AVX-512 instructions that were used by Intel in advertising, and were those in fact available at the time when the benchmarks were ran?

>>If it would be a fix then it would be that something that was advertised did not work, and now it does

Those CPUs were not compliant with their own published spec, now they are - it is absolutely a fix.


> Yes, but once it has shipped and people may have come to depend on it it will break stuff, not fix stuff.

That may apply to every change, including things everybody agrees on to be bug fixes. If, for example, you improve the number of correctly returned bits for computing sin, that can break programs, for example games that want to keep world models in exact sync across systems.

From what I read here, intel didn’t advertise this feature and it wasn’t easily discovered. If so, I don’t think customers have any claim against Intel for the CPUs.

_If_ motherboard vendors advertised/promoted it (could be as simple as blogging about it), I would think people who bought a motherboard because it allows activating this feature will have a case against them (in the EU and possibly elsewhere, the seller is responsible for the product being fit for purpose, not the manufacturer, so it would be the seller, but let’s ignore that)

Legally, there also is the issue who applies that update. From what I read, that’s the motherboard. Here again, I would say that, if customers have a case, it would be against whomever sold them the motherboard (e.g. if that silently applies the update) I don’t see any indication that Intel, as a CPU manufacturer, forces existing customers to install this.


To add to this - even if the motherboard manufacturer allows this despite Intel's advice, in their stock configuration none of those CPUs allow AVX-512 instructions out of the box. You need to knowingly and conciously go into the BIOS and disable all efficiency cores first, to make this option even appear. So "as sold" the product doesn't support AVX-512 instructions and the advertising is absolutely correct. Just like you can overclock the CPU but it doesn't come overclocked out of the box(and Intel assumes no liability if you do overclock it).


Intel very specifically said that AVX-512 instructions will not be available only a few weeks before the Alder Lake launch.

While it cannot be said that Intel advertised AVX-512 for Alder Lake, at all previous disclosures it was said that the Golden Cove cores have AVX-512 and the Gracemont cores do not have it.

It was clearly said that in hybrid configurations AVX-512 will be disabled, because for Microsoft it is a too difficult task to implement scheduling on a system with heterogeneous cores.

Whether AVX-512 can be enabled by disabling the Gracemont cores was not said, but everybody interpreted that saying nothing about this means that it will be possible to enable AVX-512, because Alder Lake is a replacement for Rocket Lake and Tiger Lake, both of which have AVX-512.

This is one of a very few cases, if not the only case, when Intel replaced a CPU product without preserving backward software compatibility.

If this was their intention from the beginning, then they certainly should have said it much earlier, not just immediately prior to launch.


>>Whether AVX-512 can be enabled by disabling the Gracemont cores was not said

Reading up on it, I was under the impression that's exactly how it worked, no? If you disable the efficiency cores in BIOS, the enable AVX-512 option would appear on selected few motherboards. You can't have all cores enabled and keep AVX-512 enabled at the same time.


This was possible on most motherboards at launch.

Now however, Intel has issued a BIOS update that no longer allows enabling AVX-512 when the Gracemont cores are disabled.

The motherboards produced from now on will have the new BIOS version.

Keeping the original BIOS on the existing Alder Lake motherboards is not a good choice, because the new BIOS version also improves stability in certain memory configurations.


Good example. It’s like buying a car and finding out it has a nice radio that was not advertised. After a few months the car dealership sends someone to break into the car and rip it off. Fair enough since it wasn’t advertised, right?


Well, breaking into your car is still illegal, so no, not fair enough.

More like you buy a car without paying for a satellite radio(or that feature isn't advertised and isn't in the spec sheet), and then that feature gets removed next time you bring the car in for service. That is absolutely fine.


Based on the lawsuit about Tesla removing features from a used car it seems like it's not fine.


This has nothing to do with advertisement. You should not be able to retroactively make products that you've already sold to people be less useful, whether or not the feature you're clawing back was advertised.


I disagree completely. The product as sold wasn't compliant with its own technical spec sheet - now after the update it is. The feature isn't supported by that CPU and it should have never been exposed to the consumer. If you discovered that the CPU has 8 cores despite being sold as a 6 core, then removing 2 cores with a BIOS update wouldn't be "making the product less useful" either. It just makes the product exactly as specified in its technical documentation - and that is how it should be.

Let me play a devil's advocate here - what if using the feature actually damages the processor after a while? AVX instructions always generate a tonne of heat. Maybe that's the reason why it was meant to be unsupported in the first place. Should Intel be allowed to fix the CPU and bring it in line with spec, or is that "making the product less useful"?

Edit: also - Intel isn't forcing anyone to install this BIOS update. If you want to keep it with AVX instructions available, at the cost of disabling all efficiency cores - sure, keep it that way.


> If you discovered that the CPU has 8 cores despite being sold as a 6 core, then removing 2 cores with a BIOS update wouldn't be "making the product less useful" either.

Yes it would.

> what if using the feature actually damages the processor after a while?

Tell the owners this, and let them choose whether or not to take that risk.

> Intel isn't forcing anyone to install this BIOS update.

But then you'll be forever vulnerable to whatever the next variant of Spectre is. You can't cherry pick just the good parts of the update while excluding the bad parts.




Consider applying for YC's Fall 2026 batch! Applications are open till July 27.

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: