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AMD 3rd Gen EPYC Milan Review

anandtech.com

11–20 of 109 posts

Re: AMD 3rd Gen EPYC Milan Review

#13
post #5

Why so little L3 cache on the competition?

EPYC is a split L3 cache. Any particular core only benefits from 32MBs of L3, the 33rd MB is "on another chip". (EDIT: Zen2 was 16MBs, Zen3 is 32MBs. Fixed numbers for Zen3)

As such, AMD can make absolutely huge amounts of L3 cache (well, many parallel L3 clusters), while other CPU designers need to figure out how to combine the L3 so that a single core can benefit it from it all.

Re: AMD 3rd Gen EPYC Milan Review

#14
post #2

how is a 300W cpu cooled in a server environment? just high rpms and good environmentals? ive stayed on intel with my workstation so i can keep a virtually passive and quiet heatsink without having to go water

Typical servers are 1U or 2U high boxes. 1U=44.5 mm and each box is "full depth", so around 700 mm long (sometimes more), and ~450 mm wide. The 1U boxes typically just have a block of copper with a dense bunch of fins on them as a CPU cooler, while 2U designs usually incorporate heatpipes.

Lots of airflow.

High-density systems are usually 2U, but with four dual-socket systems per chassis.

Re: AMD 3rd Gen EPYC Milan Review

#15
post #2

how is a 300W cpu cooled in a server environment? just high rpms and good environmentals? ive stayed on intel with my workstation so i can keep a virtually passive and quiet heatsink without having to go water

To put it in perspective, the Intel Xeon 6258R is rated at 205W. Servers have oodles of (likely airconditioned) airflow so this isn't a problem.

Re: AMD 3rd Gen EPYC Milan Review

#17
post #2

how is a 300W cpu cooled in a server environment? just high rpms and good environmentals? ive stayed on intel with my workstation so i can keep a virtually passive and quiet heatsink without having to go water

When I worked in HPC in Tromsoe, arctic Norway, one of local supercomputers was liquid cooled and the heat used warmed up some buildings on the university campus.

Re: AMD 3rd Gen EPYC Milan Review

#18
post #10
post #3

Earlier quoted context omitted.

Yeah, noise is relatively unimportant so they tend to use a ton of extremely high RPM fans and big hunks of copper, from what I've seen.

And the DC staff wears hearing protection when they're working among the racks.

That still blows my mind. Coming from telecom where everything prior to the #5 ESS was convection cooled, a happy office is a quiet office.

Data got weird.

Re: AMD 3rd Gen EPYC Milan Review

#19
post #8

There must be a typo on the 74F3 price. US$2900 for it is a steal.

I found it in the original press release (price for !K units, of course) https://ir.amd.com/news-events/press-releases/detail/993/amd...

Still seems like a typo, it doesn't make any sense that the 24 / 48 would be priced between the 8 / 16 and the 16 / 32. Either the prices of the 73 and 74 were swapped or the tag is just plain wrong. "2900" is also very suspiciously round compared to every other price on the press release.

Re: AMD 3rd Gen EPYC Milan Review

#20
post #10
post #3

Earlier quoted context omitted.

Yeah, noise is relatively unimportant so they tend to use a ton of extremely high RPM fans and big hunks of copper, from what I've seen.

And the DC staff wears hearing protection when they're working among the racks.

I wish that hearing protection had been required or at least offered when I used to visit data centers frequently. They made a big deal of the fire suppression training, but never even suggested ear plugs. 20 year-old me had no idea how bad that noise was for my ears. I hope the staff there were wearing plugs, but it was never apparent.
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