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GMP damaging Zen 5 CPUs?

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Re: GMP damaging Zen 5 CPUs?

#161

Post by taneq »

gruez wrote: post #50
einpoklum wrote: post #44

Earlier quoted context omitted.

Wow, I can't believe how BS this TDP is! I feel like a total idiot! I've always assumed it's sorta-kinda a tight upper bound on power consumption, perhaps with some allowance for "imperfections" in the dissipation properties of the CPU, and that I shouldn't sweat the details. Couldn't this count as false/misleading advertizing though?

It's thermal design power, ie. it's the power that it's designed for, not absolute max.

Huh, I always thought it was “total dissipated power”. Like you’d use to spec a power supply.

Re: GMP damaging Zen 5 CPUs?

#162

Post by inejge »

sireat wrote: post #154
db48x wrote: post #133

Earlier quoted context omitted.

Nope. Remember that you cannot destroy energy. The energy you use to flip the flip flop still exists, only now it’s just disordered waste heat instead of electricity.

To be a bit flippant, you can absolutely destroy energy by creating some mass.. Then again most of us do not have particle accelerator nearby looking for Higgs boson.

>> The energy you use to flip the flip flop

> To be a bit flippant

I see what you did here :)

Re: GMP damaging Zen 5 CPUs?

#163

Post by nolok »

ndiddy wrote: post #124
spoaceman7777 wrote: post #101

Earlier quoted context omitted.

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

This is per design. On AM5 processors, there's a hotspot on the lower half of the processor where the dies that contain the CPU cores are located. Noctua recommends that AM5 users mount their coolers shifted towards the lower side of the processor for optimal cooling performance, see https://noctua.at/en/offset-am5-mounting-technical-backgroun... . You may have missed the paragraph in the article that explicitly poin…

While it is noctua advice, I don't think AMD supports that view, so it would seem correct to at least test the cpu the way the vendor recommends before making conclusions

Re: GMP damaging Zen 5 CPUs?

#164

Post by mrheosuper »

RachelF wrote: post #125
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…

Yes, this is the point - software should never be able to physically damage the hardware it is on. If it can, then the hardware is to blame.

As a FW engineer, my software has released the magic smoke a lot.

Re: GMP damaging Zen 5 CPUs?

#165

Post by akimbostrawman »

mook wrote: post #152
sitkack wrote: post #106

Earlier quoted context omitted.

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

Given that Gamers Nexus needs the ad revenue wouldn't linking to a re-upload that wouldn't give them any of that be sort of bad?

They do not "need" it since that movie was crowd funded with over 400k anyways and AdSense are pittance in comparison. They also have indirectly promoted that reupload.

Re: GMP damaging Zen 5 CPUs?

#166

Post by akimbostrawman »

RachelF wrote: post #128
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…

AMD has failed to be reliable with its Zen 4 and Zen 5 consumer CPUs, just at the same time Intel did the same with their 13k and 14k higher end CPUs. AMD is somewhat worse than Intel as their DDR5 memory bus is very "twitchy" making it hard to get the highest DDR5 timings, especially with multiple DIMMs per channel.

I don't think it's reasonable to call memory timing tweaking stability issues worse than a cpu dying from heat under normal usage.

Re: GMP damaging Zen 5 CPUs?

#167

Post by dspillett »

mook wrote: post #152
sitkack wrote: post #106

Earlier quoted context omitted.

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

Given that Gamers Nexus needs the ad revenue wouldn't linking to a re-upload that wouldn't give them any of that be sort of bad?

While they can't publish it themselves this at least achieves the goal of the information being spread, along with the knowledge that it was their investigative team that did the work in the first place.

But yes, once they reedit and republish themselves (or manage some sort of appeal and republish as-is) then of course linking to that (and a smaller cut of the parts they've had to change because Bloomberg were litigious arseholes, if only to highlight that their copyright claim here is somewhat ridiculous) would be much better.

Re: GMP damaging Zen 5 CPUs?

#168

Post by Mistletoe »

mrheosuper wrote: post #122
themafia wrote: post #78

Earlier quoted context omitted.

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

When something is uploaded to the internet, it won't be easy to take it down. Ask Beyonce.

Can you explain further about Beyoncé? Do you mean the elevator video where her sister attacks Jay Z?

Re: GMP damaging Zen 5 CPUs?

#169

Post by crote »

mook wrote: post #152
sitkack wrote: post #106

Earlier quoted context omitted.

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

Given that Gamers Nexus needs the ad revenue wouldn't linking to a re-upload that wouldn't give them any of that be sort of bad?

YouTube ad revenue isn't as high as you'd think. A very significant part of their income comes from in-video sponsors and merchandise sales.

Re: GMP damaging Zen 5 CPUs?

#170

Post by imtringued »

db48x wrote: post #153
dcrazy wrote: post #135

Earlier quoted context omitted.

Energy cannot be created or destroyed, but it can enter and leave an open system. When I lift a 10kg box 1 meter in the air, I don’t raise its temperature at all, and I only raise mine a tiny bit, yet I have still done work on the box and therefore have imparted it energy. The energy came from food I ate earlier, and was ultimately stored in the box as gravipotential energy. Is this not analogous to storing energy in…

Yes, but only briefly. When you study the thermodynamics of information you’ll discover that it’s actually erasing information that has a cost. Every time the CPU stores a value in a register it erases the previous value, using up energy. In fact, every individual transistor has to erase the previous state on basically every clock cycle. Curiously there is a minimum cost to erase a single bit that no system can go be…

>In fact, every individual transistor has to erase the previous state on basically every clock cycle.

This is incorrect in both directions.

Only transistors whose inputs are changing have to discharge their capacitance.

This means that if the inputs don't change nothing happens, but if the inputs change then the changes propagate through the circuit to the next flip flop, possibly creating a cascade of changes.

Consider this pathological scenario: The first input changes, then a delay happens, then the second input changes so that the output remains the same. This is known as a "glitch". Even though the output hasn't changed, the downstream transistors see their input switch twice. Glitches propagate through transistors and not only that, if another unfortunate timing event happens, you can end up with accumulating multiple glitches. A single transistor may switch multiple times in a clock cycle.

Switching transistors costs energy, which means you end up with "parasitic" power consumption that doesn't contribute to the calculated output.

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