The 64 Core Threadripper 3990X CPU Review: In The Midst Of Chaos, AMD Seeks Opportunityby Dr. Ian Cutress & Gavin Bonshor on February 7, 2020 9:00 AM EST
Frequency, Temperature, and Power
A lot of questions will be asked about the frequency, temperature, and power of this chip: splitting 280W across all the cores might result in a low all-core frequency and require a super high current draw, or given recent reports of AMD CPUs not meeting their rated turbo frequencies. We wanted to put our data right here in the front half of the review to address this straight away.
We kept this test simple – we used our new NAMD benchmark, a molecular dynamics compute solver, which is an example workload for a system with this many cores. It’s a heavy all-core load that continually cycles around the ApoA1 test simulating as many picoseconds of molecular movement as possible. We run a frequency and thermal logger, left the system idle for 30 seconds to reach an idle steady state, and then fired up the benchmark until a steady state was reached.
For the frequencies we saw an ‘idle’ of ~3600 MHz, which then spiked to 4167 MHz when the test began, and average 3463 MHz across all cores over the first 6 minutes or so of the test. We saw a frequency low point of 2935 MHz, however in this context it’s the average that matters.
For thermals on the same benchmark, using our Thermaltake Riing 360 closed loop liquid cooler, we saw 35ºC reported on the CPU at idle, which rose to 64ºC after 90 seconds or so, and a steady state after five minutes at 68ºC. This is an ideal scenario, due to the system being on an open test bed, but the thing to note here is that despite the high overall power of the CPU, the power per core is not that high.
This is our usual test suite for per-core power, however I’ve condensed it horizontally as having all 64 cores is a bit much. At the low loads, we’re seeing the first few cores take 8-10W of power each, for 4.35 GHz, however at the other end of the scale, the CPUs are barely touching 3.0 W each, for 3.45 GHz. At this end of the spectrum, we’re definitely seeing AMD’s Zen 2 cores perform at a very efficient point, and that’s even without all 280 W, given that around 80-90W is required for the chipset and inter-chip infinity fabric: all 64 cores, running at almost 3.5 GHz, for around 200W. From this data, we need at least 20 cores active in order to hit the full 280W of the processor.
We can compare these values to other AMD Threadripper processors, as well as the high-end Ryzens:
|AMD Power/Frequency Comparison|
|3990X||64||280 W||10.4 W||4350||3.0 W||3450|
|3970X||32||280 W||13.0 W||4310||7.0 W||3810|
|3960X||24||280 W||13.5 W||4400||8.6 W||3950|
|3950X||16||105 W||18.3 W||4450||7.1 W||3885|
The 3990X exhibits a much lower power-per-core value than any of the other CPUs, which means a lower per-core frequency, but it isn’t all that far off at all: less than half the power for only 400 MHz less. This is where the real efficiency of these CPUs comes into play.
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WaltC - Friday, February 7, 2020 - linkAbove I meant to say that "In the past I've seen much better reviews from AT,"--you guys going to get a decent editing system for the news section anytime soon?
Irata - Friday, February 7, 2020 - linkGood point. Check OEM workstations like the Dell Precision 7920 and what is the installed OS ? Windows 10 for workstations. And that's for the lowest end 6C6T Xeon Bronze model.
The OS version's name kinda gives it away.
Irata - Friday, February 7, 2020 - linkYou could use a car comparison test as an analogy: if you are comparing a two seater to a sedan and your conclusion is that the sedan's passenger seat is more spacious, you are missing an important point - the sedan has space for three passengers, the two seater only for one, i.e. you can do things with the sedan that you cannot with the two seater.
29a - Friday, February 7, 2020 - linkThey always halfass AMD reviews, just look at EVERY Ryzen release.
sandtitz - Saturday, February 8, 2020 - linkYou have some good points there.
No software can scale up to infinite number of threads, and is 128-way already beyond some of the software tested? Some numbers saw regressions for whatever reasons.
I appreciate this article mostly for the Windows 10 Pro vs. Workstation/Enterprise benchmarking since I always thought the difference was in licensing and max CPU/Mem support.
I'm sure there are going to be enthusiasts and business users who have a need for 64 core CPU and wouldn't know the difference between Windows Pro and Workstation and would just go for the cheaper if the hardware doesn't surpass what the Pro license allows:
I've delivered some fully loaded HP Zbook laptops to end users and they had the Win 10 Workstation license from the factory. Since the CPU (E-2186M) nor the memory (64GB) didn't even approach the Pro limits I was a bit perplexed but didn't think too much of it. Perhaps HP engineers had internally benchmarked and found out speed differences?
jospoortvliet - Sunday, February 9, 2020 - linkThe real question is why anyone expects a consumer os to do well with such a cpu... even the workstation version of Windows is a joke when compared to the Linux performance: https://www.phoronix.com/scan.php?page=article&...
A 30-60% difference is no joke, and shows how big the gap between win and Lin still is. This cpu is simply too “pro” for Windows...
sandtitz - Sunday, February 9, 2020 - linkWell, that's where the Win10 Pro Enterprise/Workstations comes to play.
Had you read this Anandtech article you'd see how much faster it is than the plain Win10Pro.
Mr. Larabel didn't use the Enterprise version for testing. This is quite understandable since Microsoft doesn't make it clear that there is a tremendous performance boost.
tuxRoller - Saturday, February 15, 2020 - linkhttps://www.phoronix.com/scan.php?page=article&...
While this is using Clear Linux as reference, its advantage over Windows Enterprise ranges from 7-29% (geometric mean) with 16 - 64(+SMT) cores, respectively.
valinor89 - Monday, February 10, 2020 - linkThe baffling tittles and subtittles are references to Sun Tzu's "The art of war", I believe.
alysdexia - Monday, May 4, 2020 - linki9-9900T is more efficient and thriftier than Threadrippers.