Live data from Hacker News

GMP damaging Zen 5 CPUs?

gmplib.org

1–10 of 240 posts

Re: GMP damaging Zen 5 CPUs?

#3
Looking at the AM5 pinout[0], it looks like those pins are VDDCR and VSS. There might be a little bit of PCIe sprinkled in towards the outer edges, but I'm not 100% on the orientation of this pinout vs the orientation of the CPU. I don't know anything about electricity so I've got nothing else to add.

[0] https://upload.wikimedia.org/wikipedia/commons/2/2d/Socket_A...

Re: GMP damaging Zen 5 CPUs?

#4
As there is ongoing drama with Zen 5 and power issues, there are people with the instruments and the motivation to investigate this. You should consider contacting Gamers Nexus, and help them to get your test suite running. They can measure power draw and do a thermal analysis of this CPU, and they'd likely be eager to do it, given the possibility of making a bunch of dramatic YouTube content about design flaws in widely used hardware. That's pretty much their whole schtick in recent years.

> Modern CPUs measure their temperature and clock down if they get too hot, don't they?

Yes. It's rather complex now and it involves the motherboard vendor's firmware. When (not if) they get that wrong CPUs burn up. You're going to need some expertise to analyze this.

Re: GMP damaging Zen 5 CPUs?

#6
"We suspect that GMP's extremely tight loops around MULX make the Zen 5 cores use much more power than specified, making cooling solutions inadequate."

I feel like if this was heat related, the overall CPU temperature should still somewhat slowly creep up, thereby giving everything enough time for thermal throttling. But their discoloration sure looks like a thermal issue, so I wonder why the safety features of the CPU didn't catch this...

Re: GMP damaging Zen 5 CPUs?

#7
The room temperature or precise way the paste was applied should not matter. Modern CPUs have very advanced dynamic voltage and frequency scaling (DVFS), which accounts for several sensors, including temperature.

These big x86 CPUs in stock configuration can throttle down to speeds where they can function with entirely passive cooling, so even if the cooler was improperly mounted, they'd only throttle.

All that to say, if GMP is causing the CPU to fry itself, something went very wrong, and it is not user error or the room being too hot.

Re: GMP damaging Zen 5 CPUs?

#8
post #4

As there is ongoing drama with Zen 5 and power issues, there are people with the instruments and the motivation to investigate this. You should consider contacting Gamers Nexus, and help them to get your test suite running. They can measure power draw and do a thermal analysis of this CPU, and they'd likely be eager to do it, given the possibility of making a bunch of dramatic YouTube content about design flaws in wi…

He's a bit sensationalist, yes, but I am thankful that he saved us from buying affected Intel CPUs.

Re: GMP damaging Zen 5 CPUs?

#9
Could be the power supply and load profile?

I've heard some really wild noises coming out of my zen4 machine when I've had all cores loaded up with what is best described as "choppy" workloads where we are repeatedly doing something like a parallel.foreach into a single threaded hot path of equal or less duration as fast as possible. I've never had the machine survive this kind of workload for more than 48 hours without some kind of BSOD. I've not actually killed a cpu yet though.

Re: GMP damaging Zen 5 CPUs?

#10
That looks like a combination of improperly mounting the heatsink and noctuna being wrong in their recommendation to offset it. I’d imagine for gaming cooling one side more makes sense but my completely uneducated guess is that GMP is working a different part of the CPU than gaming does.
Post reply on HN