Review AMD Ryzen 9 3900 Review: a Taste of Eco Mode

Gillerer

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Sep 23, 2013
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I believe an AMD representative has stated that AMD truncates the advertized clock speeds - removing the (mostly irrelevant) +50 MHz; That's why a CPU whose actual boost frequency is 4.35 GHz has a "4.3 GHz" printed on the box and in marketing materials. I think the rationale was along the lines of "it's prettier" or "it's easier to take in", or something.

Due to the variations in motherboards, the 10 MHz digit isn't significant anyways; just a 100.5 MHz base clock would add +21.5 MHz to CPU speed at a 43 multiplier.
 
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Agree, publishing idle power is relevant, but anyone building a plexbox/nasbox/HTPC is going to opt for a much lower end CPU.

Not for me, I want more cores for transcoding. It takes about 2000 passmarks for every CPU encoded stream, so the 3900x can do 15 simultaneous streams. The 3900 will presumably do around 12 streams give or take.

GPU encoding looks terrible in Plex at low bitrates, like 3-6mbps, with tons of macroblocking on fast scenes. CPU encoding looks nice and clean at those bitrates. It might downgrade to 720p at those bitrates, but at least it's a clean image.

Another thing people do is use these processors as servers for virtual machines, again with the computers running 24/7. Idle power consumption matters again in this case as places like california have expensive electricity.

Also, some people can only have 1 computer, and not have a dedicated plexbox or NAS server. So they use their computer for gaming, work, video editing etc.... But leave it turned on 24/7 to act as a plex or file server. My coworker does this.

It would be awesome when reviewing CPU's in the future to have idle power consumption and the passmark score. It's something reviewers have been neglecting lately on most websites, and hard information to find.
 

PaulAlcorn

Managing Editor: News and Emerging Technology
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Feb 24, 2015
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Not for me, I want more cores for transcoding. It takes about 2000 passmarks for every CPU encoded stream, so the 3900x can do 15 simultaneous streams. The 3900 will presumably do around 12 streams give or take.

GPU encoding looks terrible in Plex at low bitrates, like 3-6mbps, with tons of macroblocking on fast scenes. CPU encoding looks nice and clean at those bitrates. It might downgrade to 720p at those bitrates, but at least it's a clean image.

Another thing people do is use these processors as servers for virtual machines, again with the computers running 24/7. Idle power consumption matters again in this case as places like california have expensive electricity.

Also, some people can only have 1 computer, and not have a dedicated plexbox or NAS server. So they use their computer for gaming, work, video editing etc.... But leave it turned on 24/7 to act as a plex or file server. My coworker does this.

It would be awesome when reviewing CPU's in the future to have idle power consumption and the passmark score. It's something reviewers have been neglecting lately on most websites, and hard information to find.

You're right, I feel it is a glaring omission, but hard to measure correctly. We ARE adding it though in some fashion. I solicited some suggestions here:
View: https://twitter.com/PaulyAlcorn/status/1189735229285707776


feel free to weigh in either here or there with ideas of what you would like to see. Sorry for the delay on adding idle power, things have been...busy.
 
You're right, I feel it is a glaring omission, but hard to measure correctly. We ARE adding it though in some fashion. I solicited some suggestions here:
View: https://twitter.com/PaulyAlcorn/status/1189735229285707776


feel free to weigh in either here or there with ideas of what you would like to see. Sorry for the delay on adding idle power, things have been...busy.

Yea, that would be awesome.

Personally I would just load windows, install all drivers and updates including motherboard driver updates and bios's. Set it to power savings plan or balanced and not install any programs. Let the machine sit for 45minutes.

Then measure the average power over say 10 minutes to get the idle power draw.
 

bloodroses

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You're right, I feel it is a glaring omission, but hard to measure correctly. We ARE adding it though in some fashion. I solicited some suggestions here:
View: https://twitter.com/PaulyAlcorn/status/1189735229285707776


feel free to weigh in either here or there with ideas of what you would like to see. Sorry for the delay on adding idle power, things have been...busy.


Would using something like Linux (command line or a bare window manager) be an option for testing idle power consumption since as you said Windows is well, Windows? It'd at least give a ballpark figure relative to (I assume) what Windows would use as well and be more consistent. You'd have to of course mention in the test that Linux is being used instead of Windows.

Another option could be something like Hiren's BootCD.
 
Apr 27, 2020
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Note that there's also a 65W / 6 core / 12 thread Ryzen 9 3900 out there.


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