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Comment by yAnonymous | Hacker News Reader

Agreed, they're great. If only they weren't so unreliable with Linux. First the segfault bug and then there's still random freezes in idle state:

https://community.amd.com/thread/225795

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The thread linked above has a fix in the latter problem that actually seems to point to the power supply, and that is likely why this seems to be hit or miss: "Because your system still freezes, it could be due to cross loading problems which can result in the power supply turning off when a load changes or result in voltages becoming out of specification causing system crashes and hangs. entire CCX or Core complex is taken down."

Setting "typical current idle" in "Power Supply Idle Control" in the BIOS seems to solve the problem here. Comments in the kernel bug report regarding this also show that this apparently solves the problem.

https://bugzilla.kernel.org/show_bug.cgi?id=196683

We run Linux on all of 18 of our new AMD machines and it works.

To be fair, the bug is random and your machines are new.

This is still a problem, discussed on the Linux Kernel bug tracker. Some recently introduced BIOS settings that increase idle power draw seem to help, though.

https://bugzilla.kernel.org/show_bug.cgi?id=196683

Wow, thanks for that thread. I just hit the "the system just goes out to lunch with no errors" issue again a few days ago on a ryzen server I have at home. This is even after an RMA months ago for the same problem. AMD support has been less-than-stellar, still waiting for their first reply this go-around.

Just how common is this? Three ryzen/linux machines here and they've been rock solid.

I believe only very early silicon was affected. AMD replaced CPUs for people on request. If you google you can find the affected datecode visible on the CPU. I have an early Ryzen from the next date and it doesn't have any issues.

AMD tightened up manufacturing at Week 25 and the incidence rate is significantly reduced after that point, but there is no date range (or factory code) on the 1000-series processors that is guaranteed to be unaffected and I recommend that everyone test their processor just to be sure.

I've seen about a dozen reports of faulty post-week-25 processors crop up in the AMD Community Forum and on Reddit from different users. Which is of course a lot better than pre-week-25 where the overwhelming majority of units are faulty. Of course, most users aren't testing for it in the first place, especially since the newer processors were widely (and incorrectly) reported to be "fixed", so it's hard to say.

https://community.amd.com/thread/215773?start=1635&tstart=0 (user jcoiner, 1726PGT)

https://community.amd.com/thread/215773?start=1725&tstart=0 (user scorpio810, 2x 1728SUS)

https://community.amd.com/thread/215773?start=1770&tstart=0 (user ryzlin, 1733PGT)

https://community.amd.com/thread/215773?start=1785&tstart=0 (user flyinryzen1700, 1737SUS)

https://community.amd.com/thread/215773?start=1830&tstart=0 (user skimba 1725PGT, user xtronom 1728PGT)

https://community.amd.com/thread/215773?start=1860&tstart=0 (user jc_yang, 1742SUS)

https://community.amd.com/thread/215773?start=1875&tstart=0 (user fedor_s 1726SUS, user karabojkov 1741SUS+1737SUS, user spiffy 1748PGS)

https://www.reddit.com/r/Amd/comments/76q7ne/got_a_defective... (user grosbof 1733SUS)

https://www.reddit.com/r/Amd/comments/7ar15o/psa_amazon_is_s... (user triplesal, 1733PGS)

https://www.reddit.com/r/Amd/comments/7ar15o/psa_amazon_is_s... (user istockporno, 1726PGT)

I am guessing that this was finally squashed for good in the 2000-series stepping.

Incidentally, there have been reports of the latest patch of Battlefield One having strange random crashes on Ryzen 1000-series but not 2000-series or Intel processors, that is reportedly fixed by disabling SMT, and I'm wondering if that's another manifestation of the segfault bug. It's hard to say, and the reality is the first-gen silicon will never be 100% trustworthy. Buy 2000-series processors instead, it's worth it for the peace of mind.

"I recommend that everyone test their processor just to be sure."

How does one do the test?

The classic test needs to be run under Linux but you can use a USB stick.

https://github.com/suaefar/ryzen-test

There is also a Windows variant that may be more sensitive than the Linux variant but fewer people have used it so YMMV.

https://github.com/corngood/kill-ryzen-win

I have a build using a Ryzen5 1600X + MSI X370 Gaming Plus + Nvidia 1070 GPU with Ubuntu 16.04 installed.

I get lockups once every 2-3 days. I was convinced the lockups were caused by a Logitech wireless keyboard, but the lockups persisted even after trying several different keyboards.

I got my Ryzen 5 soon after release. I really want to love this chip but the lockups are killing me and so painful to debug. I will try disabling C6 and see if this helps!

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