[AlexMarvel]

I am starting to use OpenFoam, fluent, and other CFD software, but my current laptop is too old to run CFD software. So I decide to buy a new laptop for writing code, using Solidworks, mesh generation. As for performing the simulation, I will do it on the server at my university.

My question is: For writing code, using Solidworks, mesh generation, and running some simple cases, How should I choose the CPU and GPU?

My current choice is between Lenovo 15.6" Legion 7 and Lenovo Legion 5. Here are the Key Features

Legion 7:

2.6 GHz Intel Core i7-10750H Six-Core
32GB DDR4 RAM | 1TB M.2 NVMe SSD
15.6" 1920 x 1080 240 Hz IPS Display
NVIDIA GeForce RTX 2070 Max-Q
Legion 5:

AMD® Ryzen™ 7 4800H Processor (2.90 GHz, Max Boost up to 4.20 GHz, 8 Cores, 16 Threads, 8 MB Cache)
15.6" FHD (1920 x 1080) IPS, anti-glare, 250 nits, 120Hz
8 GB DDR4 3200MHz
512 GB PCIe SSD + 1 TB 7200 RPM HDD
NVIDIA® GeForce® GTX 1650 Ti 4GB

[AlexMarvel]

test for eamil alerts at 2020.07.20

[flotus1]

The only noteworthy application here is solidworks. Some of its features -especially realview- can only be enabled on GPUs that are supported officially. Which is mostly the professional line of GPUs like Quadro and Radeon Pro. However, there is a workaround for consumer GPUs: search solidworks real hack.
In terms of performance, a GTX 1650TI is more than enough for any of the tasks you mentioned.

For CPU performance, it does not really matter if you choose the latest offerings from AMD or Intel. On a per-core performance metric, they are pretty similar.
You probably won't get much use out of more than 6 cores, so spending more for 8 cores is not worth it in my opinion.

The second laptop only has 8GB of RAM, configured in single-channel mode. I highly recommend upgrading this to at least 16GB, and dual-channel mode. This is something you can easily do yourself.

[AlexMarvel]

I heard that there could be some compatibility issues when using AMD CPU, have you ever experienced this kind of issue?

[flotus1]

What kind of issue exactly are you talking about?
If you are really worried about that kind of stuff, just buy Intel.

[Habib-CFD]

A laptop with desktop hardware!

EON15-X AMD Gaming Laptop ~1700$

Processors : AMD Ryzen 7 3700X 8-Core 3.6GHz (4.4GHz Max Boost)
Display Type : FHD 1920 x 1080 15.6" IPS level 144Hz Matte Display
Graphics Cards : NVIDIA GeForce RTX 2060 6GB GDDR6 Max-P [VR Ready]
Memory : 16GB ORIGIN PC Approved DDR4 3200MHz (2X8GB)

[AlexMarvel]

I am not sure, just heard about there might be some compatibility issues when using AMD CPU to run professional software, do you have any related experiences?

[CFDfan]

Originally Posted by AlexMarvel

I am not sure, just heard about there might be some compatibility issues when using AMD CPU to run professional software, do you have any related experiences?

I've heard the same and it's related to the parallel processing. The best way would be to contact the technical support of the software you are going to use and get the information from them.

Also 16gB RAM is not enough for serious jobs, 32 or 64gB are more appropriate

[flotus1]

Could any of you please point to the sources of such rumors. Or at least try to be a little more specific. "Professional software", "parallel processing" and "AMD CPUs" is not much to work with. Because that's exactly how these rumors proliferate. The next guy goes ahead posts that kind of unsubstantiated nonsense somewhere else, because he read it here.

[CFDfan]

Originally Posted by flotus1

Could any of you please point to the sources of such rumors. Or at least try to be a little more specific. "Professional software", "parallel processing" and "AMD CPUs" is not much to work with. Because that's exactly how these rumors proliferate. The next guy goes ahead posts that kind of unsubstantiated nonsense somewhere else, because he read it here.

a guy is complaining here:

https://html.developreference.com/ar...h+intel+mpi%3F

"Intel maintains the largest share of processors in the world's top 500 supercomputers at 95.2 percent" (2018), and as you know the supercomputers use thousands CPUs operating in parallel.

The CFD codes (I am familiar with) use Intel's MPI and therefore a software package that's been optimized for Intel-specific instructions will perform better on Intel CPU in parallel processing (high-performance computing (HPC)).

Finally, a guy buys a PC to use it for CFD tasks for at least 4-5 years I believe and yet it is a major expense. Isn't it safer for him to buy it with a CPU he hasn't heard any bad rumors about (regardless if they are true or not).

[Simbelmynë]

Originally Posted by CFDfan

a guy is complaining here:

https://html.developreference.com/ar...h+intel+mpi%3F

"Intel maintains the largest share of processors in the world's top 500 supercomputers at 95.2 percent" (2018), and as you know the supercomputers use thousands CPUs operating in parallel.

EPYC Rome was released in august 2019 and is seeing an increase right now. Intel dominates, but then again, how many new systems do you think appears each year on top 500? It's not the cheapest investments and a large part of the investment is political.

Originally Posted by CFDfan

The CFD codes (I am familiar with) use Intel's MPI and therefore a software package that's been optimized for Intel-specific instructions will perform better on Intel CPU in parallel processing (high-performance computing (HPC)).

This means nothing. Only real performance is important. It is difficult to say anything without doing benchmarks. For a well known CFD code with a reasonably large user base you can compare CPUs here.

Originally Posted by CFDfan

Finally, a guy buys a PC to use it for CFD tasks for at least 4-5 years I believe and yet it is a major expense. Isn't it safer for him to buy it with a CPU he hasn't heard any bad rumors about (regardless if they are true or not).

This is just rubbish. Something a fanboy would state. Obviously you can find many complaints about any hardware so this does not make any sense. If you think Intel is flawless then you have clearly not followed the latest security problems (there are many).

You pick hardware based on available facts not on what some random dude says (me included).

[flotus1]

First, let me reiterate what I stated earlier: there is absolutely nothing wrong with choosing a latest-gen Intel CPU over an AMD CPU in a laptop, for whatever reason. Performance figures, particularly for CFD workloads, will be pretty close. So if you have any doubts whether an AMD CPU might cause you any trouble, just pick a laptop with an Intel CPU for that extra peace of mind.

That being said, there is just so much wrong with the arguments presented here, I wasn't sure if it was worth a rebuttal. Most of it seems to taken from this playbook: https://en.wikipedia.org/wiki/List_of_fallacies
But anyway, since I asked for it,...

a guy is complaining here:
https://html.developreference.com/ar...h+intel+mpi%3F

A two-liner question from someone who seems to be not particularly tech-savvy. This boils down to "I tried nothing, and it doesn't work". This is the kind of question I usually avoid answering due to lack of effort on behalf of OP.
Interesting side-note: this question deals with Opteron CPUs. Which are completely and utterly obsolete in 2020. Current-gen AMD CPUs have nothing in common with them, apart from the AMD brand name.
Stretching that logic just a bit, I could claim that Intel CPUs can't do floating point arithmetic right, therefore avoid Intel CPUs. Which would be nonsense in 2020.
Also, and this really should not need to be stated in a forum where nearly everyone has a background in mathematics, engineering or physics: correlation does not imply causation.

"Intel maintains the largest share of processors in the world's top 500 supercomputers at 95.2 percent" (2018), and as you know the supercomputers use thousands CPUs operating in parallel.

Numbers aside, I fail to see what the first part of that statement has to do with the latter part. And what do the top500 supercomputers have to do with a laptop?
So much is true, Intel still dominates the top500 list. Although with new entries into that list, the ratio is more like 10:1 than 20:1 https://www.servethehome.com/top500-...tems-analysis/
But overall, the argument "most top500 supercomputers run on brand X, therefore buy brand X for your laptop" is a double-whammy in the logical fallacy department.

The CFD codes (I am familiar with) use Intel's MPI and therefore a software package that's been optimized for Intel-specific instructions will perform better on Intel CPU in parallel processing (high-performance computing (HPC)).

The CFD codes I am familiar with do not use Intel MPI, or at least offer alternative MPI implementations.
But again, we are looking at a logical fallacy here. Just because a tool has brand X in its name, does not mean that using brand Y hardware to run it won't work. See e.g. these benchmarks, where AMD Epyc CPUs outclass Intel CPUs while using an Intel compiler: https://www.anandtech.com/Show/Index...-of-the-decade

Finally, a guy buys a PC to use it for CFD tasks for at least 4-5 years I believe and yet it is a major expense. Isn't it safer for him to buy it with a CPU he hasn't heard any bad rumors about (regardless if they are true or not).

By that logic, these rumors being mentioned in this exact thread should be enough to avoid brand Y. No evidence needed, spreading a rumor is enough.
But again, see my initial statement about the CPU choice for laptops.

[CFDfan]

Originally Posted by flotus1

First, let me reiterate what I stated earlier: there is absolutely nothing wrong with choosing a latest-gen Intel CPU over an AMD CPU in a laptop, for whatever reason. Performance figures, particularly for CFD workloads, will be pretty close. So if you have any doubts whether an AMD CPU might cause you any trouble, just pick a laptop with an Intel CPU for that extra peace of mind.

That being said, there is just so much wrong with the arguments presented here, I wasn't sure if it was worth a rebuttal. Most of it seems to taken from this playbook: https://en.wikipedia.org/wiki/List_of_fallacies
But anyway, since I asked for it,...


A two-liner question from someone who seems to be not particularly tech-savvy. This boils down to "I tried nothing, and it doesn't work". This is the kind of question I usually avoid answering due to lack of effort on behalf of OP.
Interesting side-note: this question deals with Opteron CPUs. Which are completely and utterly obsolete in 2020. Current-gen AMD CPUs have nothing in common with them, apart from the AMD brand name.
Stretching that logic just a bit, I could claim that Intel CPUs can't do floating point arithmetic right, therefore avoid Intel CPUs. Which would be nonsense in 2020.
Also, and this really should not need to be stated in a forum where nearly everyone has a background in mathematics, engineering or physics: correlation does not imply causation.


Numbers aside, I fail to see what the first part of that statement has to do with the latter part. And what do the top500 supercomputers have to do with a laptop?
So much is true, Intel still dominates the top500 list. Although with new entries into that list, the ratio is more like 10:1 than 20:1 https://www.servethehome.com/top500-...tems-analysis/
But overall, the argument "most top500 supercomputers run on brand X, therefore buy brand X for your laptop" is a double-whammy in the logical fallacy department.


The CFD codes I am familiar with do not use Intel MPI, or at least offer alternative MPI implementations.
But again, we are looking at a logical fallacy here. Just because a tool has brand X in its name, does not mean that using brand Y hardware to run it won't work. See e.g. these benchmarks, where AMD Epyc CPUs outclass Intel CPUs while using an Intel compiler: https://www.anandtech.com/Show/Index...-of-the-decade


By that logic, these rumors being mentioned in this exact thread should be enough to avoid brand Y. No evidence needed, spreading a rumor is enough.
But again, see my initial statement about the CPU choice for laptops.

This discussion is not productive anymore for AlexMarvel who is asking opinions what hardware to buy. If you have AMD in your PC/laptop and it works fine with ..... CFD code then just say so. Your personal experience shared here would have been much more useful than your vigorous defense of AMD.

What I was saying is that Intel is a market leader in HPC (high performance computing, parallel processing, whatever you want to call it), the CFD codes I know use intel's MPI and there is no risk if one buys Intel CPU. I don't know if AMD works or no, my personal experience is that Intel CPUs work fine.
What I am sure however is that 8gB in the AMD configuration AlexMarvel selected on the very top is not enough. It should be at least 32gB, but I would (personally) make sure the laptop has enough memory slots to be upgraded to 64gB.

[flotus1]

This is not about defending the products of one particular company, let alone the company itself. How pathetic would that be for someone who is not on their payroll
I have said it three times already in this thread, and I will say it once more: nothing wrong with a laptop with an Intel CPU. But you should not be pushed into buying that option with arguments that have no basis in reality.
It is a defence against fearmongering with -let's call them questionable- arguments.
By the way, a tactic that no longer allows you to take the high road afterwards.

You only have experience with Intel CPUs. That's cool. But it does not put you into a position to judge whether CPUs from different companies work just as well. Digging up a 10 year old, non-conclusive forum post does not change that. I asked for sources in hopes of learning something new, maybe an interesting article to read that slipped under my radar.
It should have gone without saying, but since apparently it didn't: yes, I have experience with both Intel and AMD CPUs. And no surprising incompatibilities to report.

[CFDfan]

Originally Posted by flotus1

This is not about defending the products of one particular company, let alone the company itself. How pathetic would that be for someone who is not on their payroll
I have said it three times already in this thread, and I will say it once more: nothing wrong with a laptop with an Intel CPU. But you should not be pushed into buying that option with arguments that have no basis in reality.
It is a defence against fearmongering with -let's call them questionable- arguments.
By the way, a tactic that no longer allows you to take the high road afterwards.

You only have experience with Intel CPUs. That's cool. But it does not put you into a position to judge whether CPUs from different companies work just as well. Digging up a 10 year old, non-conclusive forum post does not change that. I asked for sources in hopes of learning something new, maybe an interesting article to read that slipped under my radar.
It should have gone without saying, but since apparently it didn't: yes, I have experience with both Intel and AMD CPUs. And no surprising incompatibilities to report.

Good on you. Your last sentence would have been good enough to avoid all this time wasting discussion