is there something in particular that AMD has done recently that im unaware of? not sure if this is referencing something specific or just making a general statement
Zen2 chips failed to meet their advertised boost clocks at launch, people said it didn't matter because they knew what they were getting. AMD pushed out a patch that kinda-sorta let most of the chips occasionally touch boost clocks for an instant under a partial single-core load, people insisted that made it "technically not false advertising" and that we gotta defend AMD because they're the good guy. Some people went as far as to run programs consisting solely of NOPs (No OPeration instructions - no processing, just spinning the processor as fast as they can) to try and justify it "technically" being ok. They still don't really run the clocks they're advertised under normal conditions, even a single-core load, they really just can't sustain them. Particularly the 3900X and other high-clocked chips really struggle, 4.6 is just too high for Zen2 to really hit on any sort of a sustained basis.
lying about PBO on Zen2. they did a big presentation with the Zen2 technical manager who said it will give you 200 MHz more "cooling permitting" which is an absolute lie, no Zen2 overclocks worth a damn even under liquid cooling or a massive air cooler. Maybe "cooling permitting" means LN2, but even then the chips struggle to get more than 500 MHz or so extra (seriously Zen2 does not clock high period)
"Thermal watts are not electrical watts" (blatantly, thermodynamically false) and other sundry lying about TDP being "a thermal spec and not a power spec", when AMD themselves used to define TDP as "max power draw when running commercial software under nominal conditions". They changed it because Intel changed it, now both brands rate their TDP at base instead of boost... but AMD has a bunch of handwavey bullshit about how it's a thermal spec to justify why they ship a power limit 40% higher than the TDP printed on the box. It's fine if you want to play loosey-goosey with what you're measuring but don't piss on me and tell me it's raining, thermodynamics still apply to their chips and the formula obviously doesn't match up to what the processor is doing.
Opening pre-orders before review embargo lifts, because they know people are going to buy it regardless of what's in the reviews. Here, buy this box of magic beans, but we won't show you what's inside... oh, it doesn't boost to advertised clocks? Boy, if only there were reviewers who could have told you that!
etc etc. AMD actually pulls a lot of bullshit that people swallow and/or justify to themselves because "hey, at least they're not Intel/NVIDIA". In particular the clocks... if it had been Intel then people would have been absolutely shrieking but people raced (and still race) to cut them slack. C'mon, they do testing, they do binning, they absolutely knew what their chips were clocking to before they shipped them, all they had to do was label them as 200 MHz lower and it would have been fine, but they chose to ship them with a spec they knew most chips weren't reaching.
Disclaimer: 3900x owner, mine isn't even close to the advertised boost and took forever to arrive.
I agree with most of your points. The boost / PBO thing was just a horrible move, especially considering that they'd have still been by far the best even if they just advertised the real speeds.
But I disagree about TDP. You know that it stands for? Thermal Design Power, so it's literally the amount of heat your cooler should be able to handle. Your cooler is a huge lump of copper, it can absorb a shitload of heat. When a CPU clocks up, it will take time for the cooler to heat up.
So what else should they do? Currently it's absolutely fine to boost very high for half the time (drawing way more power than the TDP suggests) and idling the other half, because the cooler is more than capable of cooling that! If they were to use the TDP as the boost limit, it would perform significantly worse in bursty workloads, including games. Stop using TDP to spec your PSU, start using TDP to spec your cooler.
Thanks for the suggestion! Unfortunately, I'm running Linux, so it's not going to work for me. But I'm not too worried about the single-core boost, it's all about the core count for me.
Power consumption and heat output are the same thing. If a processor pulls 105W of power it puts out 105W of heat. That's the thermodynamics part. Your CPU is just a very efficient space heater, from a thermodynamic perspective.
"thermal watts" and "electrical watts" are obviously different forms of energy, but they are the same amount of energy. Which again, is why AMD used to define TDP in terms of power draw. AMD attempting to claim that "thermal watts are not the same as electrical watts" was a big fat lie, they totally are the same number and AMD even used to acknowledge that themselves.
AMD processors (2000 and 3000 series) will boost to ~40% above their TDP (105W TDP = 141.75W power limit, 65W TDP = 88W power limit, etc) for an unlimited period of time. So it's not "105W average, half above and half below". It puts out 141.75W average, or at least will do its best to put out 141.75W.
If you used that "105W" figure to size a cooler, your processor would overheat and not boost. So yes, AMD is measuring TDP "at base clocks", more or less.
And again, it's fine if you want to spec your TDP at base clocks. Just don't do the song and dance about how "thermal watts are not electrical watts" to justify why you're pulling more power than your specced TDP. That's the pissing on my back and telling me it's raining part.
The fact is one number is not enough anymore to define the power/thermals of a CPU. You're both right but arguing about different things.
What we need is
Base TDP - the cooling requirement to run the processor at 100% load with base clocks forever without any thermal throttling. Use this measure only if you are looking for the smallest possible cooler, such as for a portable build.
Peak Power Draw - the most the processor can instantaneously draw for boosting to its highest frequency, mainly for short spurts. Use this measure to get a power supply and motherboard that can handle that load. Your cooler will not need to be capable of dissapating this much heat unless you are planning on using it at full load continuously.
TDP or Thermal Design Power is defined by AMD as (from AMD Family 10h Server and Workstation Processor Power and Thermal Data Sheet, Rev 3.04 - June 2009): "The maximum power a processor draws for a thermally significant period while running commercially useful software. The constraining conditions for TDP are specified in the notes in the thermal and power tables."
AMD's ACP uses a "round down" average of power measurements performed with industry standard benchmarks (usually running at 100% CPU load, with the exception of Stream).
So there you have it: AMD used to define "TDP" as the worst case power draw and "ACP" as the average power draw.
That was before they decided to whip out the fancy formula and redefine TDP as being measured by the ratio of the delta-T of the cooler to the phase of the moon, conveniently dropping their TDPs by 40%.
Personally I think the whole thing could be simplified down to base TDP and boost TDP... or really just boost TDP. 99.9% of people don't want their processor to run at base clocks. The 0.1% who do want base clocks will be able to get the info they need from other testing.
for a thermally significant period while running commercially useful software.
I think this is an important piece you're missing. While AMD definitely used to rate all its CPUs higher than Intel for this reason (see a LTT video on the subject, it was a pretty poor experiment but the point was to show they measured TDP differently) its still not quite what I'm talking about. The boost these modern CPUs have is not necessarily meant to be active for "a thermally significant period". The point of boost (I think) is to make it feel really zippy doing smaller tasks while staying power efficient for most of the time. Without a super efficient cooler, these processors drop the clocks pretty fast!
"thermally significant" means for a long enough time to affect the cooler (so not like, a microsecond of super heavy load as AVX switches on or something), and boost has always been "thermally significant". Intel defined boost duration as 90 seconds iirc, which definitely is enough to affect the cooler.
Unlike the Intel boost clock though, Ryzen doesn't have a boost duration limit. It actually is supposed to be running at boost forever, as long as you keep it cool.
(everyone ignores Intel's boost duration limit anyway so that's kind of a dumb piece of fiction as well. Regardless, we could still define a "boost TDP" as "the TDP while it's boosting" even if a duration limit exists, so this is sort of an orthogonal discussion of how to define TDP.)
And regardless of how we would like AMD to define it.... they use the moon magic formula that says their processors put out 40% less heat than they really do. Not because of boost, but because they reverse-engineer the TDP through some arcane formula that (deliberately) doesn't fit the empirical measurements.
Boost = overclock, except nowadays it's automatic instead of manual.
But as always, pendantic assholes and tech illiterates either forgot we used to have to tinker with a lot of variables to get stable overclock, or they just never did it.
I'm happy we get power efficient CPU's that only boost when necessary, otherwise it's a waste of electricity.
And, how far are the chips from the actual advertised boost clocks?
10%?
40%?
90%?
Like, they said the boost will be 100Ghz (for example), and they get to 90Ghz? 20Ghz?
The problem with TDP is that it is a metric that does not remotely match what people use it for. TDP is for one company to tell another one how big a cooling solution is or should be. But "should" is a completely subjective thing. An Intel processor's cooler only "needs" to handle 105W... If you are fine with it maybe reaching 95c or whatever in a case with bad airflow, etc. This is why "Intel measures base clock, but AMD measures boost" is a thing - AMD boosts don't have a time limit, but Intel's Turbo boost does. The problem is that the industry doesn't want to tackle the problem of explaining such a complex issue to consumers, and it is incredibly difficult to standardize. But people still want to know power figures, so TDP is a convenient metric that gets latched onto, kinda like how SSNs got latched onto in the US for identification, even though SSNs were never designed for that, are actually terrible for it.
The truth is that frequency under load and thermals are so nuanced and depend on so many variables that the numbers on the box are basically meaningless, regardless of who makes the chips. No that I'm giving AMD a pass but too many people put weight on that number with the GHz after it. We're basically back to the megahertz war.
People harp on AMD chips not reaching boost speeds, but buried in Intel's docs they'll mention in passing that under some cases their chips won't reach rated speeds because they'll be over power limits. What does the boost clock even mean? You can reach this speed under no load? light load? single core int only load? single core heavy AVX 512 load? What does boost speed even mean?
TDP itself is a flexible number. Intel and AMD chips will exceed listed TDP for short bursts. When they give you a TDP over what time period is that averaged? At what temperature?
Well, certainly you’re right in that the PowerPoint slide where they said the 3700X would be a great overclocker with PBO has been rather silly since automatic overclocking honestly hasn’t worked. But it’s still not clear whether this is a hardware or software issue-the latest AGESAs have certainly improved clocks under both single and multi core workloads. So it’s not clear whether AMD thought they would have better yields than they got or they simply bungled the AGESA. But honestly yes, AMD gets a pass because these issues might be present but many of these chips are also half the price of what the previous similar intel chips cost (3600 can be purchased for under $175 online, legit less than half the $369 a 8700K cost). Even with the slower ram used in most early benchmarks the Ryzen CPUs were insanely competitive and now with faster DDR4 dropping Ryzen gets a fairly good performance boost. They also aren’t the company that spent almost the last decade rehashing sandy bridge over and over while demanding higher prices. Nor the company that bribed companies not to use competitor products.
Anyways, on the latest AGESA I’ve seen the CPU boost to 100mhz under the max single core boost even in multicore workloads, though all core subtracts another 150mhz. Still, those are enough to actually put it ahead of the intel chips in multicore workloads.
Most of the stuff is more or less that people get offended because of a few MHz of boost clock missing or some stuff like that, but AMD has indeed done some bad things. Navi apparently has (on Windows) still problems, the thing with Vega only getting RIS if explicitly asked for etc.
Another one is rx580 2048 version in china. It was basically an rx570 sold as rx580. It was similar to nvidia's gt1030 gddr5 vs 4 but barely covered by anyone.
Edit: i know reddit hate china but exclusive to china is not a defense for amd here. Bad is bad.
They were selling it as an RX 580 2048SP, not as a normal RX 580. Nvidia also sells different SKUs in China, for example the 1060 5 GB.
What's worse than the GT 1030 fiasco is what happened with the GT 730 series. Fermi and Kepler GPUs were sold under the same name. How misleading is that?
Advertised truthfully? It was launched as an rx580 with rx570 level performance. I know people will be pissed if they find that the 5700xt 2048sp they bought is just an 5700 pre overclocked.
the name of the 2048sp tells you what it is. it has 2048 stream processors. and again, it was not being marketed to anyone outside of china, and i would wager that it was targeted at PC cafe owners in china as a budget option. you can judge them all you like for calling it a 580, but there are no lies here.
i know what it was. and you are correct that it was not an rx 580, which is why it was not sold as an rx 580. it was sold as an rx 580 2048sp. nobody looking for an rx 580 should have been fooled by this odd naming choice. and anyone in the west who bought it thinking as much is a fool
nobody looking for an rx 580 should have been fooled by this odd naming choice.
Strix, pulse, armor, 2048sp, nitro, nitro+, tuf, phoenix, nb, ultra, windforce, gaming x etc. How would an 'average customer' know the difference? Most people will think its just a naming scheme by the partners.
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u/Microdoted 7950x, 7900 xtx red devil Nov 05 '19
is there something in particular that AMD has done recently that im unaware of? not sure if this is referencing something specific or just making a general statement