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GMP damaging Zen 5 CPUs?

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Re: GMP damaging Zen 5 CPUs?

#151

Post by dcrazy »

marshray wrote: post #142
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?

Clocking and changing register states requires charging and discharging the gate capacitance of a bunch of MOSFET transistors. The current that results from moving all that charge around encounters resistance, which converts it to heat. Silicon is only a "semi" conductor after all. You are correct that there is energy bound in the information stored in the chip. But last I checked, our most efficient chips (e.g., usi…

Thank you for encouraging me to go on this educational adventure. I have now heard of Landauer’s principle, which says each bit of information releases 2.9e-21 joules when destroyed: https://en.wikipedia.org/wiki/Landauer%27s_principle

Re: GMP damaging Zen 5 CPUs?

#152

Post by mook »

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

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?

Re: GMP damaging Zen 5 CPUs?

#153

Post by db48x »

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…

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 below. It’s extremely small, billions of times smaller than the amount of energy our CPUs use every time they erase a bit, but it exists. Look up Landauer’s Limit. There is a similar limit on the maximum amount of information stored in a system which is proportional to the surface area of the sphere that the information fits inside. Exceed that limit and you’ll form a black hole. We’re no where near that limit yet either.

Re: GMP damaging Zen 5 CPUs?

#154

Post by sireat »

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.

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.

Re: GMP damaging Zen 5 CPUs?

#155

Post by mook »

Twirrim wrote: post #73
mk_stjames wrote: post #28

Earlier quoted context omitted.

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.

That was SpeedStep? By the time AMD got to it it was just sort of expected and didn't have a fancy name, as far as I know.

Or maybe I'm thinking of something else entirely…

Re: GMP damaging Zen 5 CPUs?

#156

Post by fithisux »

toast0 wrote: post #53
fithisux wrote: post #20

[flagged]

> The x86-64 ISA is a POS BTW. > It needs major refactoring. The backwards compatibility is killing the platform. People have been saying that for 30 years at this point. You can dislike the ISA all you want, but the platform doesn't seem to be dieing all that fast, and compatibility helps it live. Compatibility is how you sell chips: windows on arm doesn't sell because people are concerned about running their apps;…

The Intel ISA CPUs have too many features for backwards compatibility.

This puts a lot of design strain, CPU have to support everything, have to emulate behaviors.

Too much bloat on the CPU.

Re: GMP damaging Zen 5 CPUs?

#158

Post by frabert »

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.

Or Barbra Streisand

Re: GMP damaging Zen 5 CPUs?

#159

Post by Seattle3503 »

esseph wrote: post #136
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.

Same with secure boot for me. Kinda makes sense that a BIOS upgrade would wipe the config. Its that or manage schema migrations.

Re: GMP damaging Zen 5 CPUs?

#160

Post by userbinator »

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.

but have the effect of significantly increasing clock speed and power.

Ironically, if these failures are due to excessive automatic overvolting like what happened with Intel's a year ago), worse cooling would cause the CPU to hit thermal limits and slow down before harmful voltages are reached. Conversely, giving the CPU great cooling will make it think it can go faster (and with more voltage) since it's still not at the limit, and it ends up going too far and killing itself.

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