CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > General Forums > Main CFD Forum

Software works weird; Processor 3995WX

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 21, 2022, 10:02
Question Software works weird; Processor 3995WX
  #1
New Member
 
Ilya
Join Date: Oct 2019
Posts: 8
Rep Power: 5
offroader10052 is on a distinguished road
Hello.

I ask for advice.

I bought an AMD Ryzen Threadripper PRO 3995WX processor and can't use it to its full potential.

Problem:

The same task in Ansys CFX is solved at different speeds.

Each new run of the solution gives a solution at a different speed.

test 1 - 3200 seconds
test 2 - 900 seconds
test 3 - 7000 seconds
test 4 - 1400 seconds

How to achieve the same minimum solution time?

PC specifications
- AMD Ryzen Threadripper PRO 3995WX (64 physical cores, 128 threads);
- 128 GB RAM;
- 512 SSD samsung evo;
- no throttling occurs, temperature 50-55 C;
- Windows 10 x64;
- Ansys 19.1.

Did not help:

- disable hyper trading

- disable turbo boost

- reinstall win to another copy

- ssd replacement

- Installing another version of Ansys 2021

- installation of all driver and OS updates.

Other programs run fine on this PC with the same repeatable results (benchmarks, video encoding, rendering).
offroader10052 is offline   Reply With Quote

Old   July 21, 2022, 18:45
Default
  #2
Senior Member
 
Join Date: Oct 2011
Posts: 195
Rep Power: 13
naffrancois is on a distinguished road
Can you provide more info on the test case you are running ? How many cells ? Which model ? How many threads are you using ?
naffrancois is offline   Reply With Quote

Old   July 22, 2022, 03:32
Default
  #3
New Member
 
Ilya
Join Date: Oct 2019
Posts: 8
Rep Power: 5
offroader10052 is on a distinguished road
Quote:
Originally Posted by naffrancois View Post
Can you provide more info on the test case you are running ? How many cells ? Which model ? How many threads are you using ?
2.500.000 cells
I count in CFX
Hydrocyclone of standard design.
Includes oil and water.
I have run successfully this model before on another computer
I tried testing on 4, 10, 12, 16 cores (threads)
offroader10052 is offline   Reply With Quote

Old   July 22, 2022, 04:11
Default
  #4
Super Moderator
 
flotus1's Avatar
 
Alex
Join Date: Jun 2012
Location: Germany
Posts: 3,167
Rep Power: 43
flotus1 has a spectacular aura aboutflotus1 has a spectacular aura about
Which memory are you using exactly? How is it populated on the motherboard? Which motherboard? Which version of Windows 10?
flotus1 is offline   Reply With Quote

Old   July 22, 2022, 04:29
Default
  #5
New Member
 
Ilya
Join Date: Oct 2019
Posts: 8
Rep Power: 5
offroader10052 is on a distinguished road
Quote:
Originally Posted by flotus1 View Post
Which memory are you using exactly? How is it populated on the motherboard? Which motherboard? Which version of Windows 10?
DDR4 ECC REG
The motherboard has 8 memory slots.
The processor has 8 memory channels.
I'm using 4 32gb memory slots.
Windows 10 Pro x64
offroader10052 is offline   Reply With Quote

Old   July 22, 2022, 05:01
Default
  #6
Super Moderator
 
flotus1's Avatar
 
Alex
Join Date: Jun 2012
Location: Germany
Posts: 3,167
Rep Power: 43
flotus1 has a spectacular aura aboutflotus1 has a spectacular aura about
There should be a memory population guideline in your motherboard manual. Following this is important when using less than 8 DIMMs.
Regardless, you need 8 identical DIMMs to use the full capabilities of this processor. High runtime variance is a direct result of not populating all memory channels. Whether this is the only issue here, I can't tell. But it is definitely a contributing factor.
flotus1 is offline   Reply With Quote

Reply

Tags
ansys, cfx, solution

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Inverse and Transient Heat Transfer Problem on commercial software: is it possible? rogbrito Main CFD Forum 1 February 19, 2019 03:11
Inverse and Transient Heat Transfer Problem on commercial software: is it possible? rogbrito CFX 1 January 29, 2012 18:48
[Other] What software should i learn? - Meshing Anima ANSYS Meshing & Geometry 2 November 14, 2011 12:53
New software for simulating laminar flows HectorRedal Main CFD Forum 1 April 27, 2011 14:59
Waterhammer software Andris Skattebo Main CFD Forum 1 July 18, 1998 22:01


All times are GMT -4. The time now is 14:51.