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Comment by vdfs | Hacker News Reader

AMD is making good CPUs, but i had an issue with Ryzen 5 1600 that left me with a bad experience with AMD. It's was my first ever build and i used this CPU, all good, but from time to time the Linux Desktop i use will freeze, hard reboot is the only fix. I noticed that this happen when i left the PC idle and the screen turn off, i tried everything and just accepted that this is a bug in KDE/Ubuntu/Kernel/Motherboard/RAM or GPU, not in my wildest thinking thought it would be the CPU.

Turns out it was the CPU and how crappy AMD handle C-states that save energy, i had to turn them completely off and that resolved the issue (In AMD defense, freezing the entire OS do save a lot of energy)

This was exactly 2 years ago, and i had the issue for almost a year before figuring out the fix. I wonder if the new generation have this problem too?

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> Turns out it was the CPU and how crappy AMD handle C-states that save energy

From my experience, Intel is no better.

I have a 4 year old laptop with an Intel CPU that has the same problem, it was never fixed by Intel. [see EDIT]

For the first 3 years of use I just accepted the fact that my laptop would randomly freeze and I would have to reboot it.

One day, I got sick of it and started digging into forums until I found a way to avoid the specific c-state (by modifying kernel boot parameters) that caused the issue.

EDIT: Apparently, it's getting fixed now. Just 5 years late, issue was reported in 2015 https://bugzilla.kernel.org/show_bug.cgi?id=109051

I’ve just been through this exact thing with a 3200G on Ubuntu 19 and 20. Took months to disgnose. Extremely painful. Ended up replacing the RAM and motherboard before finally determining the problem was with the CPU. Disabling C-states helped but didn’t resolve the issue. Tried a bunch of other things too, none of which ultimately worked.

In the end I switched to a 3700X; so far the problem hasn’t reoccurred. No doubt it will now that I’ve posted about it (fool me twice, shame on me).

Worth pointing out that 3xxxG parts are Zen+ and not Zen 2 like all other Ryzen 3000 parts. So the CPU in the 3200G is very different from the one in a 3700X.

I stopped using Ubuntu 10 years ago, when I had a weird issue. Out of nowhere computer locked up and required a hard reset. It took a while when I figured out that issue originated with Intel WiFi card. I eventually found the bug, it turned out that kernel crashed whenever the adapter sensed an 802.11n packet (the protocol was very new at the time so it wasn't everywhere yet). Ubuntu still decided to go ahead with the release, yet hold off on including freshly released major version of Open Office (I think version 3), because of stability. This was extremely frustrating, because there was no fix and no option to rollback to older version. So that was when I dropped this POS and used a different distro. I'm wondering if that's again Ubuntu issue and not CPU.

Yeah. Who knows. It’s just an anecdote, really. But one that hopefully saves someone months of tedium.

There were more issues, but that one was what pushed me over the edge.

I constantly had problems when attaching/deataching external monitor to my laptop, once in a while it wouldn't switch, or various parts of desktop (like task bar etc) would move around.

When they introduced PulseAudio, it wasn't ready at the time, so there were a lot of audio problems back then.

Overall the experience with Ubuntu was that every new release was taking some old bugs away and replacing them with new ones.

I hope things improved since then.

I've been running a 3400G since last fall on Debian with a custom kernel to get the latest video drivers. It's been stable until a few freeze ups in the past week. I'd pin the blame on Ubuntu.

Surprisingly, the solution for the first gen Ryzens / 1600AFs is not allowing the power supply idle voltage to go into low power mode. Check your BIOS for it.

It turns out many PSUs don't handle low CPU power states well, and disabling C6 just prevents the CPU from being able to idle (and consequently, boost) properly. I've had perfect uptime with my 1600AF in a storage node since discovering this.

All my computers were Intel based except for one. It was an Athlon64 X2 from ~2006 and I also felt something was wrong when running Linux. Random crashes happened quite often, I never got to know the cause. Performance was not amazing either, despite my previous computer being 4 years older.

I've never had a problem running Intel based systems with Linux. So, even though everybody's talking about how good AMD is right now, and why you should buy one for your next rig, and how good are AMD graphic cards with open drivers instead of the nVidia binary blobs... I sincerely don't see any reason to ditch what has been working OK and make the switch when preparing a new build. Should I?

Yes, you should. AMD is significantly different than it was almost 14 years ago. They wipe the floor with Intel that's still using their years old 14 nm process. AMD simultaneously has higher performance, more cores, lower energy usage and lower cores. It is categorically better in all fields.

Yes, for the technical reasons alone, I'd be switching to AMD. And I guess a lot has changed in 15 years, sure, but as a Linux user, comments reporting issues like these is what worries me. Compared to the mostly hassle-free Intel experience, to me buying AMD gear sounds almost like a lottery.

* lower cost, not lower cores

As far as anecdotal evidence goes, I had a Linux desktop built around a 64-bit Athlon in 2004-2006 - as the primary, it saw plenty of use, but I don't recall any random crashes.

At Ryzen's launch mobo vendors weren't investing a lot into the platform because they were largely burned by previous AMD generations that failed to compete with Intel.

It wasn't until Ryzen 2000 / 3000 in particular that board vendors took the AMD stack seriously again.

I remember at release getting ram working on Zen 1 was a nightmare. Nowadays you can throw almost any stick to 3733mhz on Zen 2 no problem.

Yeah, early RAM support on Zen 1 sucked. It was definitely fair for vendors not to want to plow huge amounts of money in at that point, as the Bulldozer-era CPUs sucked in a profound manner. Definitely glad for those first few AGESA updates that got things like XMP fully working on my early X370 board.

My 1800X did the same thing. I was able to RMA it and get a replacement that worked fine. It's only the early chips that had this issue.

AFAIK this goes back to the AMD graphics driver; I just built my wife a Ryzen 3200G / B450 system and she has had a couple of spontaneous reboots too. I did burn in using an old AMD 6970 card instead of the built in graphics and it did fine with that for me; but of course that card wont run the games she wants so we're hoping for a fix too.

Having a TR 2970WX at work with the same issue. You must just disable the lower C-states, freezing the machine when coming up from sleep.

At home I've had a 3950x now for about six months and no such issues with the CPU at all. It just works and runs nicely. No freezes, no problems.

I have seen this when running Linux desktop on older AMD CPUs.

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