Question Anandtech.com article on 13900k and 7950x power scaling

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adamge

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It's an interesting article, but IMO severely crippled by the reliance on "configured" power limit rather than measuring power usage. It's even more frustrating when one of the datapoints is measured power usage, so the author has access to this data.

In this scenario where configured power limits are basically hand waving guidelines, measured power usage (specifically, average power usage by the CPU during the benchmark run) is the only useful, meaningful, and concrete way to analyze the performance results relative to the power usage.
 
Jul 27, 2020
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I myself skipped Skylake entirely due to being fed up with small performance improvements and nearly upgraded to a Zen 3 rig, but I held out in the end for a massive Broadwell-E to Raptor Lake i9 upgrade.
Yeah. Mine was Ivy Bridge to Broadwell and then Alder Lake on Z790 (not built yet though coz Broadwell doesn't seem limiting to me for the time being).
 
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Just Benching

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95°C means that the cooler already cannot dissipate the heat the CPU produces easily. It struggles.
Not at all, the problem is not the cooler, the problem is the die and the ihs that can't transfer that much heat. There is no cooler on the market that doesn't "struggle" at 330 watts. Tomshardware tested the LT720, basically the best AIO right now, and it hit 100c at 315 watts.

If what you said was true then there is no cooler on the planet that can handle a 7950x, since it basically hits 95c regardless. Obviously that's not how it works.

How much heat can it dissipate if you wanted the CPU to be 70°C?

No idea, around 200 watts I assume.
 
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Carfax83

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Ive also bought every single zen cpu except zen 3, but nowadays intel offers much better products for my needs. But mentioning that gets some people triggered it seems

Like I said, this board is heavily AMD dominated. To be honest, Raptor Lake caught a lot of people by surprise, including myself. A lot of people expected Zen 4 to pummel RPL into oblivion, that's how much hype was being built around Zen 4.......until the official AMD presentation, which deflated most of the hype and embarrassed certain leakers and a few people on this forum.

Zen 4 is still a very good CPU, but like you, I find that RPL fits my needs perfectly. And the thing I love the most about RPL, is how easy it is to customize and tweak; especially when it comes to voltages and power consumption.
 

Just Benching

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Like I said, this board is heavily AMD dominated. To be honest, Raptor Lake caught a lot of people by surprise, including myself. A lot of people expected Zen 4 to pummel RPL into oblivion, that's how much hype was being built around Zen 4.......until the official AMD presentation, which deflated most of the hype and embarrassed certain leakers and a few people on this forum.

Zen 4 is still a very good CPU, but like you, I find that RPL fits my needs perfectly. And the thing I love the most about RPL, is how easy it is to customize and tweak; especially when it comes to voltages and power consumption.
Really?I always knew RPL will be pretty much a boosted up ALD, i kinda knew what to expect. Zen 4 is what surprised me, i expected the pcores to dominate zen 4 because the gap between a pcore and a zen 3 was huge in both performance and efficiency, but zen 4 did very well, surpassing my expectations. Still loses to pcores but its much closer than i expected

We had a thread over at tpu testing pcore vs zen 3 core and yeah, was pretty nutty. It took hours of tuning on an ultra binned 5950x to get anywhere close to a stock auto settings 12900k when comparing 8P vs 8 zen 3. And even at full configuration, the 12900k just destroyed everything at 35 watts. The score ALD was getting was so insane det0x thought I was cheating 😱😂
 
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We had a thread over at tpu testing pcore vs zen 3 core and yeah, was pretty nutty. It took hours of tuning on an ultra binned 5950x to get anywhere close to a stock auto settings 12900k when comparing 8P vs 8 zen 3. And even at full configuration, the 12900k just destroyed everything at 35 watts. The score ALD was getting was so insane det0x thought I was cheating 😱😂
URL?
 

Just Benching

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Just Benching

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And I did not reply to him, since its like talking to a brick, but you know I run 24/7@100% load, so 100 watts all day every day times 3 computers.
You running them stock? Cause the 7950x is less efficient than the 5950x at stock. Didn't seem to bother you :p

And of course you are running them @ 100% 24/7. Imagine using your zen 4 for browsing, it would throw your electric bills through the roof with its 52%inefficiency delta
 

Carfax83

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Really?I always knew RPL will be pretty much a boosted up ALD, i kinda knew what to expect. Zen 4 is what surprised me, i expected the pcores to dominate zen 4 because the gap between a pcore and a zen 3 was huge in both performance and efficiency, but zen 4 did very well, surpassing my expectations. Still loses to pcores but its much closer than i expected

The hype surrounding Zen 4 was unreal, and ultimately unrealistic. There were reports of a 25% IPC increase which when combined with a healthy clock speed increase, would bury anything from Intel. I think the fact that Zen 4 would have access to TSMC's 5nm process fueled the hype and made it more believable.

As for Raptor Lake, I know that Moore's Law is Dead had said that the core would be enhanced in some way from Alder Lake, but that IPC increase would be minimal and thus most of the performance increase would come from clock speeds. While this had merit, I don't think anyone was expecting Intel to tinker with the cache performance the way they did. That more than anything is what elevates Raptor Lake above Alder Lake.

Raptor Lake's L3 read cache bandwidth was nearly doubled over Alder Lake for instance, and that's huge! :eek: Just look at the cache bandwidth increases here between ADL and RPL. It's apparent that ADL was bandwidth starved and never reached it's performance potential due to the slower cache:





We had a thread over at tpu testing pcore vs zen 3 core and yeah, was pretty nutty. It took hours of tuning on an ultra binned 5950x to get anywhere close to a stock auto settings 12900k when comparing 8P vs 8 zen 3. And even at full configuration, the 12900k just destroyed everything at 35 watts. The score ALD was getting was so insane det0x thought I was cheating 😱😂

@Det0x is an exceptional tweaker, so if that made him pause and consider, it must have been exceptional :D
 
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Just Benching

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The hype surrounding Zen 4 was unreal, and ultimately unrealistic. There were reports of a 25% IPC increase which when combined with a healthy clock speed increase, would bury anything from Intel. I think the fact that Zen 4 would have access to TSMC's 5nm process fueled the hype and made it more believable.

Yeah, yesterday you mentioned it so I read some older posts and wow. The predictions people were making.....Zen 4 will win in gaming, obliterate in ST performance...that the Pcores are slower than Zen 2 (LOL!). Makes for a fun read.


Regarding the efficiency race, yeah I was surprised as well. My 12900k was pretty average to mediocre (87sp, 60 sp on the Ecores lol) and just pounded everything into the ground at 35 watts with no manual tunning. Just auto mobo settings with UV. I think that ALD was overvolted from the factory for running AVX , but then it was disabled so it had room to UV. Cause the amount of undervolting you could do to those chips was pretty insane, was running mine at 1.06 volts at stock clockspeeds, compared to the 1.28v it had at stock. RPL is nothing like that and undervolting is pretty minimal.

Honestly I dislike with a passion the decision from Intel to increase the Ecores frequency, I don't see the point. They are there for mt performance, so clockspeeds are kinda irrelevant when you have a swarm of them. But - people and reviewers pay too much attention to those CBR23 graphs, so both companies put the pedal to the metal to achieve 1st place.

EG1. I was getting 15.200 cbr23 points @ 35 watts. That was pretty nutty
 
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Thunder 57

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Yeah, yesterday you mentioned it so I read some older posts and wow. The predictions people were making.....Zen 4 will win in gaming, obliterate in ST performance...that the Pcores are slower than Zen 2 (LOL!). Makes for a fun read.

Pcores slower than Zen 2? Sounds like some straw man crap right there, along with the rest of it.
 

Markfw

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Doesn't matter if you believe it, YOU wrote it. Alongside some other gems, like that there is no way the 7950x is going to pull 230 watts :p
See, it does not exist. Yes, I did find it hard to believe that the 7950x would take 230 watts. But saying p-cores were slower than Zen2 ? That I do not believe I said. I even bought a 12700F and said they were pretty strong, thats before Zen 4 came out.
 

Just Benching

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See, it does not exist. Yes, I did find it hard to believe that the 7950x would take 230 watts. But saying p-cores were slower than Zen2 ? That I do not believe I said. I even bought a 12700F and said they were pretty strong, thats before Zen 4 came out.
Ah, but you did, you replied to carefax with some screenshots from f@h claiming that zen 2 beats pcores.

I mean it's fine, whatever, my opinion is irrelevant, if you don't think you are incredibly biased then so be it.
 

Markfw

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Ah, but you did, you replied to carefax with some screenshots from f@h claiming that zen 2 beats pcores.

I mean it's fine, whatever, my opinion is irrelevant, if you don't think you are incredibly biased then so be it.
Link my post. I will either explain it or say you are right. Otherwise it didn't happen.