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GMP damaging Zen 5 CPUs?

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Re: GMP damaging Zen 5 CPUs?

#71

Post by bayindirh »

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 what kind of dark joke is this?

Re: GMP damaging Zen 5 CPUs?

#72

Post by aidenn0 »

FuriouslyAdrift wrote: post #23

Most likely it's the motherboard. ASRock is getting nailed right now for unstable XMP and CPU voltages (it's recommended to undervolt a little just in case). The Asus Prime B650M motherboards they are using aren't exactly high end.

Can you link to a reputable source for what settings I should use on my asrock motherboard? I'd like to avoid this.

Re: GMP damaging Zen 5 CPUs?

#73

Post by Twirrim »

mk_stjames wrote: post #28
tux3 wrote: post #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 sa…

This was my first question as well- I thought it had been a long, long time since you could fry a CPU by taking away the heatsink. As in... what, AMD K6 / early Pentium 4 days was the last time I remember hearing about cpu cooler failing and frying a cpu?

It was some time around then. I remember AMD being late to it vs Intel.

Re: GMP damaging Zen 5 CPUs?

#74

Post by trebligdivad »

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…

They don't say what temperature the CPU was reporting which seems like an odd omission. Whatever the specs of your cooler etc check the temperature it's actually running at. Go by what the CPU is saying! I've got the older 3950x, and the first one died after a few months (still in warranty) with a cooler in spec, but it would go into the 90s at full load just doing big builds. I replaced the heatsink with a basic watercooler when the replacement chip arrived and it's running at least 20c cooler at full load.

Re: GMP damaging Zen 5 CPUs?

#75

Post by jeffbee »

nisegami wrote: post #24
topspin wrote: post #14

Earlier quoted context omitted.

People without a background in electronics don't appreciate what modern CPUs and GPUs are doing: the amount of current flowing through these devices is just mind blowing. With adequate cooling, a Ryzen 9 9950X is handling somewhere in the neighborhood of 150-200 amps under high load.

I initially scoffed at the 150-200 amps. But I know core voltage is usually in the neighbourhood of 1V so to draw 200W, you really would have to basically be moving 200A of current. That's wild.

What's really wild is with all the power scaling features the regulators have to step from zero to hundreds of amps in microseconds with very little overshoot. The power design for these modern systems is demanding.

Re: GMP damaging Zen 5 CPUs?

#76

Post by FuriouslyAdrift »

aidenn0 wrote: post #72
FuriouslyAdrift wrote: post #23

Most likely it's the motherboard. ASRock is getting nailed right now for unstable XMP and CPU voltages (it's recommended to undervolt a little just in case). The Asus Prime B650M motherboards they are using aren't exactly high end.

Can you link to a reputable source for what settings I should use on my asrock motherboard? I'd like to avoid this.

No more than 1.2 volts on vsoc... but YMMV.

"According to new details from Tech Yes City, the problem stems from the amperage (current) supplied to the processor under AMD's PBO technology. Precision Boost Overdrive employs an algorithm that dynamically adjusts clock speeds for peak performance, based on factors like temperature, power, current, and workload. The issue is reportedly confined to ASRock's high-end and mid-range boards, as they were tuned far too aggressively for Ryzen 9000 CPUs."

https://www.tomshardware.com/pc-components/cpus/asrock-attri...

Re: GMP damaging Zen 5 CPUs?

#77

Post by FuriouslyAdrift »

aidenn0 wrote: post #72
FuriouslyAdrift wrote: post #23

Most likely it's the motherboard. ASRock is getting nailed right now for unstable XMP and CPU voltages (it's recommended to undervolt a little just in case). The Asus Prime B650M motherboards they are using aren't exactly high end.

Can you link to a reputable source for what settings I should use on my asrock motherboard? I'd like to avoid this.

Also... reddit

https://old.reddit.com/r/buildapc/comments/1mvuzjw/alarming_...

Re: GMP damaging Zen 5 CPUs?

#78

Post by themafia »

MrGilbert wrote: post #43
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…

> [...] 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...

Re: GMP damaging Zen 5 CPUs?

#79

Post by themafia »

tux3 wrote: post #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 sa…

If the throttling is not stable it could increase stress on the part by creating a bunch of transient but large thermal cycles through the chip. It would need to have some kind of exponential backoff on throttle so it doesn't immediately try to raise the frequencies when the temperature slightly dips.

Re: GMP damaging Zen 5 CPUs?

#80

Post by db48x »

wahern wrote: post #60
db48x wrote: post #54

Earlier quoted context omitted.

No, they don’t design the chip with these numbers in mind. 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.

That seems a little too cynical. It matters how a customer might use a chip, such as the type of cooling that would be expected in a typical system using that model, and that's informed by the advertised specifications. Base clocks and the amount of SRAM also figure into TDP. No doubt there are completely arbitrary aspects to TDP driven purely by profit-focused market segmentation, but it's not just that. That said,…

No, clock speed and cache have nothing to do with TDP. AMD uses a simple formula to calculate TDP. It is the temperature of the IHS minus the air temperature measured at the cpu cooler’s intake fan, divided by a conversion faction in °C/W.

But they don’t use real temperatures from real systems. They just make up a different set of temperatures for each CPU that they sell, so that the TDP comes out to the number that they want. The formula doesn’t even mean anything, in real physical terms.

I agree that predicting power usage is far more difficult than it should be. The real power usage of the CPU is dependent on the temperature too, since the colder you can make the CPU the more power it will voluntarily use (it just raises the clock multiplier until it measures the temperature of the CPU rising without leveling off). And as you said there are a bunch of other factors as well.

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