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Unless you absolutely need the newest for some reason, I think buying CPUs which have been out for a year if not more would be the best way of avoiding hardware bugs like this, as it seems like they've also started using users for random spot-testing instead of verifying against a spec. One would hope they have plenty of esoteric and freely available x86/PC software to use for regression testing, like demoscene productions going back to the 80s (a great way to exercise opcode sequences that compilers might rarely or never create, but should still work), but with the recent CPU bugs, it feels more like "Windows/Linux/$common_OS with $common_software seems to work, ship it!"

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I think this is solid advice but hardly a guarantee. Note this is discussing Zen2, not Zen4. wikipedia says [1] Zen2 Launched 7 July 2019; 3 years ago.

[1] https://en.wikipedia.org/wiki/Zen_2

Yes, and this bug was fixed years ago. The person who stumbled upon it only did so because the correct microcode update was not being loaded.

Although the fact that there apparently exist some APUs that have not had the update applied because of shitty OEMs is very concerning.

Also AMD being shitty and not publishing microcode updates to the linux-firmware repo so users would get access to them despite crappy OEM's or users neglecting to do BIOS updates.

There have always been latent bugs in CPUs, beyond a degree of complexity it pretty much becomes a certainty.

One of the fundamentals of selling shit profitably, is that you try to sell the vast majority of what you make, one of the consequences is that the vast majority of users exist outsider of your company and after development.

So you throw some very smart people at the problems of building and validating and building and validating, and hope that no two of them makes or repeats a mistake.

Yes, there've been some disturbingly cavalier attitudes on the patchable software side towards release quality, and more recently by Boeing on the hardware side (which they proceeded to patch from the software side), but I have not seen that sort of wanton disregard for quality from AMD/Intel/NVidia.

Honestly, the fact that this is even interesting enough to show up on HN tells you enough about how frequently it happens.

Zen 2 architecture came out in 2019 and this particular processor in 2020. I don't think your advice would work here, and there are definite downsides to waiting too many years after a processor has been released to buy it.

How can you know in advance if the processor will be recently manufactured or not? I.e. what if it's been sitting on the shelf waiting to be ordered for 8 months? Or happened to have fell off a shelf into a corner of the warehouse for a year.. etc.

Edit: @empyrrhicist: ah, my mistake. I misunderstood, thinking more recently manufactured CPUs might come with updated microcode. Thanks for the quick help.

It's not about the manufacture date, its about how long that model has been commercially available so fixes can be found/made to any issues.

I misunderstood, thinking more recently manufactured CPUs might come with updated microcode.

I'm not that familiar with the details of recent CPUs, but at least on the Intel side, I believe they do as part of the stepping identifier.

Given the number of inputs, instructions, and optimizations that go into modern processors, the combinatorial explosion makes it nigh impossible to validate against a spec. To me it's more surprising that it all works as well as it does.

But it it's been almost 3 years since Zen 2 came out?

s/3 years/4 years/

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