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GMP damaging Zen 5 CPUs?

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Re: GMP damaging Zen 5 CPUs?

#131

Post by lightedman »

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.

And you're pushing that many amps across a piece of silicon roughly the size of your thumbnail all said and done.

Re: GMP damaging Zen 5 CPUs?

#132

Post by db48x »

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…

No, the TDP number doesn’t even vaguely approximate anything. You can’t use the number to predict anything, or to plan, or to estimate your electric bill, or anything like that.

Re: GMP damaging Zen 5 CPUs?

#133

Post by db48x »

dcrazy wrote: post #130
mrb wrote: post #92

Earlier quoted context omitted.

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...

I don’t understand this argument. If the CPU dissipated an equal number of watts of heat energy as it consumed from the wall, there wouldn’t be any energy left to do actual useful work. Isn’t the extra 100W accounted for by things like changing the state of flip-flops? In other words, mustn’t one consider the entropy reduction of the system as an energy sink?

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.

Re: GMP damaging Zen 5 CPUs?

#134

Post by foresto »

sitkack wrote: post #106
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...

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

That copy is missing the chapters. Here they are:

00:00:00 - The NVIDIA AI GPU Black Market

00:06:06 - WE NEED YOUR HELP

00:07:41 - A BIG ADVENTURE

00:10:10 - Ignored by the US

00:11:46 - BACKGROUND: Why They're Banned

00:16:04 - TIMELINE

00:21:32 - H20 15 Percent Revenue Share with the US

00:26:01 - Calculating BANNED GPUs

00:29:31 - OUR INFORMANTS

00:31:47 - THE SMUGGLING PIPELINE

00:33:39 - PART 1: HONG KONG Demand Drivers

00:43:14 - PART 1: How Do Suppliers Get the GPUs?

00:48:18 - PART 1: GPU Rich and GPU Poor

00:56:19 - PART 1: DATACENTER with Banned GPUs, AMD, Intel

01:06:19 - PART 1: Chinese Military, Huawei GPUs

01:09:48 - PART 1: How China Circumvents the Ban

01:19:30 - PART 1: GPU MARKET in Hong Kong

01:32:39 - WIRING MONEY TO CHINA

01:36:29 - PART 2: CHINA Smuggling Process

01:43:26 - PART 3: SHENZHEN's GPU MIDDLEMEN

01:50:22 - PART 3: AMD and INTEL GPUs Unwanted

01:56:34 - PART 4: THE GPU FENCE

02:06:01 - PART 4: FINDING the GPUs

02:15:12 - PART 4: THE FIXER IC Supplier

02:21:12 - PART 5: GPU WAREHOUSE

02:27:17 - PART 6: CHOP SHOP and REPAIR

02:34:52 - PART 6: BUILD a Custom AI GPU

02:56:33 - PART 7: FACTORY

03:01:01 - PART 8: TAIWAN and SINGAPORE Intermediaries

03:02:06 - PART 9: SMUGGLER

03:05:11 - LEGALITY of Buying and Selling

03:08:05 - CORRUPTION: NVIDIA and Governments

03:26:51 - SIGNOFF

Re: GMP damaging Zen 5 CPUs?

#135

Post by dcrazy »

db48x wrote: post #133
dcrazy wrote: post #130

Earlier quoted context omitted.

I don’t understand this argument. If the CPU dissipated an equal number of watts of heat energy as it consumed from the wall, there wouldn’t be any energy left to do actual useful work. Isn’t the extra 100W accounted for by things like changing the state of flip-flops? In other words, mustn’t one consider the entropy reduction of the system as an energy sink?

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.

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 the EM fields within the CPU?

Re: GMP damaging Zen 5 CPUs?

#136

Post by esseph »

protocolture wrote: post #129

I have a Ryzen and it ran fine until one day, after some load, it wont run at all with the virtualisation options turned on anymore. Having read all I can on the issue its largely been ignored by AMD. If its some kind of thermal runaway issue that would not surprise me.

I had a bios reset itself to defaults before, and some AMD boards don't have all the required virtualization options on by default.

I only realized this happened because every time I had ever upgraded firmware, I always had to go back and set XMP settings, one or two other things, and than cpu virt option.

Re: GMP damaging Zen 5 CPUs?

#137

Post by keanebean86 »

cogman10 wrote: post #115
bayindirh wrote: post #71

Earlier quoted context omitted.

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…

Man that was a beast of a CPU back in the day. The Conroe Intel era was amazing for the time.

That was such a fun time to be into hardware. For years Intel had the money and relationships to keep the Pentium 4 everywhere even though AMD had the better product. The P4 might edge ahead in video rendering but the Athlon would win overall and use less power.

Then Conroe launched and the balance shifted. Even the cheapest Core2Duo chips were competitive against the best P4s and the high-end C2Ds rivaled or beat AMD. https://web.archive.org/web/20100909205130/http://www.anandt...

AND those chips overclocked to the moon. I got my E6420 to 3.2ghz (from 2.133ghz) just by upping the multiplier. A quick search makes me think my chip wasn't even that great.

Re: GMP damaging Zen 5 CPUs?

#138

Post by lmm »

dcrazy wrote: post #135
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.

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…

CPUs don't store nontrivial amounts of energy, and even if storing a 1 was a significantly higher energy level than a 0 (or vice versa) there's no plausible workload that would be causing the CPU to switch significantly more 0s to 1s than 1s to 0s (or vice versa).

Re: GMP damaging Zen 5 CPUs?

#139

Post by jmb99 »

thway15269037 wrote: post #109

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…

Different use patterns will result in different temperatures. Very tight math loops (no memory/IO wait) will lead to higher temperatures than something that that relies on L2/3 cache or main memory, even though they’ll both report “100% CPU use” and probably use similar amounts of power. And, different operations will produce heat in different areas of the die; depending on physical layout, some operations might generate heat in a tiny cluster, whereas some others might generate heat in larger spread out areas. Even though both of those cases might use the same amount of power and generate the same amount of heat, the temperatures will be drastically different due to the heat concentration.

Iirc the FFT step uses AVX, and on Zen 5 that’ll be AVX-512. It should keep 100% of the required data in L1 caches, so you’re keeping the AVX units busy literally 100% of the time if things are working right. The rest of the core will be cold/inactive, so if you’re dumping an entire core’s worth of power into a teeny tiny ALU, which is gonna result in high temps. Most (all?) processors downclock under heavy AVX load, sometimes by as much a 1GHz (compared to max boost), because a) the crazy high temperatures results in more instability at higher frequencies, and b) if the clocks were kept high, temperatures would get even higher.

Re: GMP damaging Zen 5 CPUs?

#140

Post by marshray »

spoaceman7777 wrote: post #101
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

Clearly paste was squeezed out from the entire perimeter of the CPU. Offset mounting is used intentionally for this CPU.

Probably there's less paste remaining on the south end of the CPU because that's where the mounting force is greatest.

If anything, there's too much paste remaining on the center/north end of the CPU. Paste exists simply to bridge the roughness of the two metal surfaces, too much paste is a bad sign.

My guess is that the MB was oriented vertically and that big heavy heat sink with the large lever arm pulled it away from the center and north side of the CPU.

IMO, the CPU is still responsible for managing its power usage to live a long life. The only effect of an imperfect thermal solution ought to be proportionally reduced performance.

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