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GMP damaging Zen 5 CPUs?

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Re: GMP damaging Zen 5 CPUs?

#91

Post by gruez »

db48x wrote: post #82
gruez wrote: post #56

Earlier quoted context omitted.

>The marketing department picks the number they want based on how they want customers to think about the chip, and which competitors they want you to compare it against. They just plug in whatever numbers are needed into the formula so that the number comes out how they want it. Are you just describing product segmentation? ie. how the ryzen 5700x and 5800x are basically the same chip, down to the number of enabled c…

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 (eg. a bunch of AVX512 floating point operations vs a bunch of NOPs), therefore TDP is totally made up? I agree that there's a lot of factors that impact power usage, and CPUs aren't like a space heater where if you let it run at full blast it'll always consume the TDP specified, but that doesn't mean TDP numbers are made up. They still vaguely approximate power usage under some synthetic test conditions, or at the very least is vaguely correlated to some limit of the CPU (eg. PPT limit on AMD platforms).

Re: GMP damaging Zen 5 CPUs?

#92

Post by mrb »

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-...

You are correct. In fact these guys measured a maximum socket power consumption of 240 watt using a 9950X at stock settings, running prime95. So far above the "170 watt" TDP:

https://hwbusters.com/cpu/amd-ryzen-9-9950x-cpu-review-perfo...

Re: GMP damaging Zen 5 CPUs?

#93

Post by mqus »

wtallis wrote: post #42
wrs wrote: post #33

No actual die temperature measurements? That would seem a lot more relevant than the ambient temperature.

Die temperature readings aren't particularly helpful these days with desktop parts that will (depending on the power management settings) more or less keep increasing the clock speed until they reach ~90°C and just stay there. Upgrading from a bad/undersized heatsink can easily have only a tiny effect on temperature but have the effect of significantly increasing clock speed and power.

Aren't they at least useful for ruling out any anomalies there? Like the die temp being 110°C constantly? Imho the die temperature is very important here, even if not interesting.

Re: GMP damaging Zen 5 CPUs?

#94

Post by wiredpancake »

BoorishBears wrote: post #38
hnuser123456 wrote: post #29

Earlier quoted context omitted.

GN wasn't the first to break the story the 13/14th gen was defective. The thousands and thousands of users experiencing the issues collectively noticed pretty quick. If anything, there was a period where he was saying "We've talked to Intel but we won't say anything yet until they do."

[flagged]

The only real problem with GN is Steve is a bit of an egotist when it comes to content creators who do less technical analysis, like LTT or Jayz.

He never really got over the stuff with Linus and doubled down on stupid things. I think they both have a great place in the tech scene and LTT's videos of recent have been a lot better quality and researched then yesteryear.

Re: GMP damaging Zen 5 CPUs?

#95

Post by lofaszvanitt »

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…

I always used the stock cooler, because it's quiet and nothing uses the cpu to its fullest :).

Re: GMP damaging Zen 5 CPUs?

#96

Post by CaptainBanger »

tpurves wrote: post #61
fxtentacle wrote: post #8

Earlier quoted context omitted.

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

Yes. When he's right, he's right. However the main issue I have with GN is how Steve tends to go full Leeroy Jenkins pitchforks and torches for 9 out of every 5 actual scandals in the tech industry.

I felt the same way, but over time I have come to respect those with the Crusader personality archetype, we need these people to do their thing and they need us to balance them out.

Re: GMP damaging Zen 5 CPUs?

#97

Post by T-A »

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...

[3] https://www.tomshardware.com/pc-components/cpus/amd-ryzen-9-...

Re: GMP damaging Zen 5 CPUs?

#98

Post by stouset »

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…

That’s a good catch, but don’t modern CPUs thermally throttle, rather than risk damage? Not that you should rely on this with an underpowered cooling solution but I would expect worse performance, not a fried chip.

Re: GMP damaging Zen 5 CPUs?

#99

Post by BearOso »

fxtentacle wrote: post #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 C…

They said it took months for each CPU to fail. Both systems used the same inadequate heatsink/fan. Then there's also the lower-end motherboards (they are not "top-quality", the brand means nothing) and the miniscule 450W power supply used in the initial configuration, which are confusingly paired with a 16-core CPU and 64/96GB of RAM.

It doesn't strike me as odd that running an extremely power-heavy load for months continuously on such configurations eventually failed.

Re: GMP damaging Zen 5 CPUs?

#100

Post by spoaceman7777 »

stouset wrote: post #98
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…

That’s a good catch, but don’t modern CPUs thermally throttle, rather than risk damage? Not that you should rely on this with an underpowered cooling solution but I would expect worse performance, not a fried chip.

Not really a lot it can do rapidly enough if there's only thermal paste on half the CPU.

It sounds like the user likely did the opposite of the "offset seating" of the heatsink that Noctua recommended.

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