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GMP damaging Zen 5 CPUs?

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Re: GMP damaging Zen 5 CPUs?

#101

Post by spoaceman7777 »

topspin wrote: 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…

All you really need to see is the picture of the CPU with thermal paste only on one half. Thermal throttling is tuned to work when there is 1. a sufficient heatsink (theirs was significantly below requirements) and 2. it is installed correctly so that its triggers for downclocking happen with the correct timing. This is just another instance of ridiculous PEBCAK error

Re: GMP damaging Zen 5 CPUs?

#102

Post by codezero »

I recently built a 9950x3d system and it definitely runs hotter/louder than my other builds. To be fair, it also has a 5090 in it, but I liquid cool the 9950 and over all the system is just hot. If I saw 165W rated on a 170W system, I think that kind of just answers it, I see no reason not to overcool a system with high end electronics on it, and there's no reason to toe the line so closely.

Re: GMP damaging Zen 5 CPUs?

#103

Post by spoaceman7777 »

topspin wrote: post #46
MrGilbert wrote: post #43

Earlier quoted context omitted.

> [...] a bunch of dramatic YouTube content [...] That framing doesn't do him and the team justice. There is (or better, was) a 3.5h long story about NVIDIA GPUs finding their ways illegaly from the US to China, which got taken down by a malicious DMCA claim from Bloomberg. It is quite interesting to watch (Can be found archive.org). GN is one of the last pro-consumer outlets, that keep on digging and shaking the tre…

For the record, I think GN is excellent and highly credible.

[flagged]

Re: GMP damaging Zen 5 CPUs?

#104

Post by lazide »

gruez wrote: post #91
db48x wrote: post #82

Earlier quoted context omitted.

Yep. The 5800X is a higher bin specifically because it can clock higher than the ones in the 5700X bin. That certainly makes them draw more power, so they give them a higher TDP number too. But the TDP doesn’t have anything to do with how much power the cpu will draw or how much heat it will generate in practice. Those numbers vary quite a lot; the CPU continuously adjusts it’s own frequency multiplier based on it’s…

>But the TDP doesn’t have anything to do with how much power the cpu will draw or how much heat it will generate in practice. Those numbers vary quite a lot; the CPU continuously adjusts it’s own frequency multiplier based on it’s own measured temperature, meaning it’ll draw more power if you cool it better. I don't get it, are you referring to the phenomenon that different workloads have different power consumption…

Apparently that’s not actually true?

Re: GMP damaging Zen 5 CPUs?

#105

Post by chaoskitty »

This isn't good. Then again, the amount of power going in to these CPUs is way too high.

Take the AlphaServer DS25. It has wires going from the power supply harness to the motherboard that are thick enough to jump a car. The traces on the motherboard are so thick that pictures of the light reflecting off of them are nothing like a modern motherboard. The two CPUs take 64 watts each.

Now we have AMD CPUs that can take 170 watts? That's high, but if that's what the motherboards are supposed to be able to deliver, then the pins, socket and pads should have no problem with that.

Where's AMD's testing? Have they learned nothing watching Intel (almost literally) melt down?

Re: GMP damaging Zen 5 CPUs?

#106

Post by sitkack »

themafia wrote: post #78
MrGilbert wrote: post #43

Earlier quoted context omitted.

> [...] a bunch of dramatic YouTube content [...] That framing doesn't do him and the team justice. There is (or better, was) a 3.5h long story about NVIDIA GPUs finding their ways illegaly from the US to China, which got taken down by a malicious DMCA claim from Bloomberg. It is quite interesting to watch (Can be found archive.org). GN is one of the last pro-consumer outlets, that keep on digging and shaking the tre…

> which got taken down Not everywhere: https://archive.org/details/the-nvidia-ai-gpu-black-market-i...

https://www.youtube.com/watch?v=ZyWelvEP_CQ

Re: GMP damaging Zen 5 CPUs?

#107

Post by johncolanduoni »

bayindirh wrote: post #71
db48x wrote: post #19

> The so-called TDP of the Ryzen 9950X is 170W. The used heat sinks are specified to dissipate 165W, so that seems tight. TDP numbers are completely made up. They don’t correspond to watts of heat, or of anything at all! They’re just a marketing number. You can't use them to choose the right cooling system at all. https://gamersnexus.net/guides/3525-amd-ryzen-tdp-explained-...

When I see the term TDP, I remember what I have read in the "Thermal Design Document" of Intel Core2Quad Q6600 and the family it belongs: > The thermal solution bundled with the CPUs is not designed to handle the thermal output when all the cores are utilized 100%. For that kind of load, a different thermal solution is strongly recommended (paraphrased). I never used the stock cooler bundled with the processor, but w…

Most states of “100% utilization” as you’d see in `top` are not 100% thermal output or even close. Cores waiting for memory accesses count as utilized in the former sense but will not produce as much heat as one that is actually using the ALU etc. That’s why special make-work like Prime95 is used for stress testing overclocking/thermals: it will saturate the cores with enough unblocked arithmetic work to generate more heat than having 1000 browser tabs open does.

Re: GMP damaging Zen 5 CPUs?

#108

Post by hpcjoe »

I noticed the comments pointing out that TDP is a marketing number, and max power draw for this part can be higher. The cooling seems to have been inadequate.

A rule of thumb I use for cooling is, you can rarely have too much. You should over-engineer that aspect of your systems. That and the power supply.

I have a 7950x, with a water block capable of sinking up to 300W. Under heavy load, I hear the radiator fans spinning up, and I see the cpu temp hover around 90-93 C. That is ok, though cooler would be better. My next build (this one is 2 years old) will also use a water block, but with a higher flow rate, and a better radiator system. I like silent systems, though I don't like the magic smoke being released from components.

Re: GMP damaging Zen 5 CPUs?

#109

Post by thway15269037 »

I don't know about GMP, but I recently built a PC with 9950X3D. As part of initial testing, I ran Prime95 for 48 hours. Everything ran stable, but I noticed that part of the tests, I think it was FFT or something like that, caused incredibly sharp increase in temp. We are talking 60C average in the rest of the test vs immediate (less than a 5 seconds) 95+ degrees when that FFT thingie started. It was very weird.

That's when I discovered actually ancient term "power virus". Anyway, after talking to different people I dismissed this weird behavior and moved on.

Reading this makes me worry I actually burned mobo in that testing.

Re: GMP damaging Zen 5 CPUs?

#110

Post by BugsJustFindMe »

T-A wrote: post #97

A quick search on the NH-U9S shows it's a compact cooler for small systems, rated for up to 140 W (see e.g. [1]). The 9950X's TDP (Thermal Design Power) is 170 W, its default socket power is 200 W [2], and with PBO (Precision Boost Overdrive) enabled it's been reported to hit 235 W [3]. [1] https://www.overclockersclub.com/reviews/noctua_nh_u9s_cpu_c... [2] https://hwbusters.com/cpu/amd-ryzen-9-9950x-cpu-review-perfo…

Noctua does not use TDP for their heatsinks and instead have CPU compatibility charts. They say it's fine, with "medium turbo/overclocking headroom". https://ncc.noctua.at/cpus/model/AMD-Ryzen-9-9950X-1831
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