Processors

[juanpc]

As the title says...

with a dual socket motherboard having asymmetric CPUs?

for example 6308 + 6386 "4+16"

etc...

has someone done tests, or knows where I can find the answer?

6000 & 7000 series Opteron & Epyc

the reason is that some softwares i need only work with a maximum of 20-cores, and don't have a way to Core limit@ before starting the program.

the software works well with 16-cores, but Not with 32.

has a lot of errors, I suspect related to the software needing Visual Studio x86,

[black_zion]

What about going with Threadripper? It's cheaper than EPYC and is 16 cores itself?

[juanpc]

the Tr 1950X looks interesting...

https://www.pcworld.com/article/3214635/components-processors/ryzen-threadripper-review-we-test-amds...

but...

#1. Motherboard Price is "the same" $500usd.

1x cpu vs. 2x cpu.

Super Micro Computer, Inc. - Aplus Products | Motherboards | H11DSi

Non -NT

A+ H11DSi Motherboard Dual AMD EPYC 7000-Series... | Acmemicro

#2. server boards & cpus have Buffered ECC memory capability, very important when using more than 32GB.

example: if you have an Amd RAMDrive with 4GB "the free versión", and Bitlock the Drive,

and has 1 tiny memory error, all information will be lost.
AMD Radeon(TM) RAMDisk

#3. problem with #1. is that CPU Throtlle if core temps are over >60°C,

is easy to Air Cool a dual 8-core CPU, than 1x 16-core CPU...

with 32nm technology like the 6300 series.

the biggest 4U Air cooler for G34 socket is OK, Supermicro SNK P0050AP4 with the optional G34 braket.

supermicro BKT-0050L-G34 socket G34 mounting bracket for... | Acmemicro

but the Biggest 3U air cooler for G34, the Dynatron A14 throttles with a 140w CPU.

"when a CPU throttles is better to leave Windows Power Options to Balanced, than Performance."

gives better results in the long run.

Example: encoding h.264

1950X base frequency is a lot faster than Epyc 7351 16-core CPU AMD EPYC 7351 Processor PS7351BEVGPAF 16Cores 32Threads... | Acmemicro

also Price is $265 lower, but those $265 extra give the ability to use Dual CPU, and ECC Memory.

8-core 7251 AMD EPYC 7251 Processor PS7251BFV8SAF 8Cores 16Threads... | Acmemicro

32-core 7601 AMD EPYC 7601 Processor PS7601BDVIHAF 32Cores 64Threads... | Acmemicro

thats the only reason for a 1950x.

there is also the Epyc P versions that do not work with dual CPU, like the Threadripper.

AMD EPYC 7351P Processor PS735PBEVGPAF 16Cores 32Threads... | Acmemicro

the Price of Windows Server 2016 is too much.

and is No Guarantee that all software will work with 32 o 64-cores.

for example: AMD RAMDrive does not work with Windows Server, only the DataRam RAMDrive versión Works,

but licenses are Not interchangeables nor upgredables.

RAMDisk - Software that Accelerates, Protects, Optimizes - Server Memory Products & Services - Datar...

most softwares have problems with more than 20-cores.

but there is not a 20-core CPU, only a 24-core 7451 AMD EPYC 7451 Processor PS7451BDVHCAF 24Cores 48Threads... | Acmemicro

for some software HyperThreading does not work well,

Real cores are definitely better.

Conclusión:

a dual 8-core Epyc CPU + Mobo Price is the same as 1950x + Mobo.

but with ECC Buffered Memory capability,

but at a lower frequency.

but 2x better cooling, when working 100% for days, weeks, months, Non-stop.

like Folding @ Home

for Windows there is Nothing better in that Price range...

Intel has dual 10-core Xeon CPU´s, and single 20-core CPU´s but Price is much higher.

F @ H for Windows is 32-bit, "x86 only", it wont work with more than 20-cores.

Alternative Downloads - Folding@home

maybe i will install FreeBSD or TrueOS on a New drive to test with 32-cores.

Index of /ftp/releases/amd64/amd64/ISO-IMAGES/11.1/

Index of /master/amd64/

Watercooling is another story.

[colesdav]

Hi,

Interesting Question...

Threadripper has the ability to turn off cores and also to disable SMT.
Please see the following article: Retesting AMD Ryzen Threadripper’s Game Mode: Halving Cores for More Performance

I will take a look to see what EPYC can do in that respect.
I have not checked yet.

I might guess you may be thinking of running some version of Linux?
If so have you tried this approach?

https://www.cyberciti.biz/faq/debian-rhel-centos-redhat-suse-hotplug-cpu/linux-turn-on-off-cpu-core-...

Cheers.

[colesdav]

Below I tested turning off cores on Linux Centos 7.3.
It appears to work with an Intel i7-4790K at least.

# lscpu

Architecture:          x86_64

CPU op-mode(s):        32-bit, 64-bit

Byte Order:            Little Endian

CPU(s):                8

On-line CPU(s) list:   0-7

Thread(s) per core:    2

Core(s) per socket:    4

Socket(s):             1

# echo 0 > /sys/devices/system/cpu/cpu6/online

# cat /sys/devices/system/cpu/online

0-5,7

# cat /sys/devices/system/cpu/offline

6

# echo 1  > /sys/devices/system/cpu/cpu6/online

# cat /sys/devices/system/cpu/online

0-7

# cat /sys/devices/system/cpu/offline

# lscpu

Architecture:          x86_64

CPU op-mode(s):        32-bit, 64-bit

Byte Order:            Little Endian

CPU(s):                8

On-line CPU(s) list:   0-7

Thread(s) per core:    2

Core(s) per socket:    4

Socket(s):             1

# echo 0 > /sys/devices/system/cpu/cpu6/online

# lscpu

Architecture:          x86_64

CPU op-mode(s):        32-bit, 64-bit

Byte Order:            Little Endian

CPU(s):                8

On-line CPU(s) list:   0-5,7

Off-line CPU(s) list:  6

Thread(s) per core:    1

Core(s) per socket:    4

Socket(s):             1

Hope this is useful...

[colesdav]

Have you checked to see if you can disable Cores / Hyperthreading in the Motherboard BIOS?
That could be an alternative if you are using Windows (you mentioned you currently use Visual Studio ... ).
Cheers.

[colesdav]

How about going single socket Motherboard. Using the above method to to disable 4 of the cores, download and run Visual Studio for Linux and get one of these:
AMD EPYC 7401P Linux Benchmarks and Review - Something Special

Bye.

[colesdav]

If you go Ryzen or Threadriipper on Windows then you have this ...
AMD Ryzen™ Master Utility for Overclocking Control | AMD
Which appears to  control how many threads or Cores are Active.

I have not seen if this is also available for EPYC but I would have thought it might be.