[newcomer_123]

Hello! I really appreciate your thread.
I'm here because I have basicly 4k to spend on a computer, and I want to make the best of it! Really appreciate your Greatest advices

Which software do you intend to use? Ansys Fluent
Are you limited by license constraints? I.e. does your software license only allow you to run on N threads? No licence constraints.
What type of simulations do you want to run? And what's the maximum cell count? Related to heat exhangers, I don't know about the maximum cell count but I expect 5-10 million.
If there is a budget, how high is it? 4000 euros for All PC + Monitors
What kind of setting are you in? Hobbyist? Student? Academic research? Engineer? Academic research + Engineering and designing a product
Where can you source your new computer? Buying a complete package from a large OEM? Assemble it yourself from parts? Are used parts an option? Can buy it from parts.
Which part of the world are you from? It's cool if you don't want to tell, but since prices and availability vary depending on the region, this can sometimes be relevant. Particularly if it's not North America or Europe. Europe.

This is the build I have done:
CPU Intel Core i9-13900K 3 GHz 24-Core Processor
CPU Cooler be quiet! Dark Rock Pro 4 50.5 CFM CPU Coole
Motherboard MSI MAG B760 TOMAHAWK WIFI ATX LGA1700 Motherboard
Memory Corsair 2 X Vengeance 64 GB (2 x 32 GB) DDR5-5200 CL40 Memory
Storage 2 X Samsung 980 Pro 2 TB M.2-2280 PCIe 4.0 X4 NVME Solid State Drive
Video Card Asus Dual GeForce RTX 3060 V2 OC Edition GeForce RTX 3060 12GB 12 GB
Case Corsair 4000D Airflow ATX Mid Tower Case
Power Supply Corsair RM750e (2023) 750 W 80+ Gold Certified Fully Modular ATX

As a complete newbie, I have many doubts about the CPU.

Thank you so much!

[wkernkamp]

Desktop configurations with just two memory channels are not so good for CFD. You should look at a dual EPYC system. Study some of the configurations other people have settled on in "Hardware".

[newcomer_123]

Originally Posted by wkernkamp

Desktop configurations with just two memory channels are not so good for CFD. You should look at a dual EPYC system. Study some of the configurations other people have settled on in "Hardware".

Thank you so much =)

I will check it!

Edit:

After having read many threads, first I understood (along with some research) how beneficial a quad-channel CPU is, the main problem being that I can only buy new parts and I don't have the money necessary for EPYC, so my comparation would be between i7-9800X and i9-13900K, the first is much older but based on what I saw I could enjoy the benefits of parallel running:


Processor Model: i7-9800X (Quad-Channel)
Number of processor cores: 8
Number of processor threads: 16
Processor Series: Intel® Core™ X-series
Processor Cache: 16.5 MB
Processor Cache Type: Smart Cache
Compatible Chipsets: Intel® X299
Processor Max Turbo Frequency: 4.4 GHz
Maximum Internal Memory Supported by the Processor: 128 GB
Memory Types Supported by the Processor: DDR4-SDRAM
Memory Speeds Supported by the Processor: 2666 MHz
Max Memory Bandwidth 85 GB/s

VS

Processor Model: i9-13900K (Dual-Channel)
Processor Family: Intel® Core™ i9
Processor Core Count: 24
Processor Thread Count: 32
Processor Operating Modes: 64-bit
High-Performance Cores: 8
Efficient Cores: 16
Processor Max Turbo Frequency: 5.8 GHz
High-Performance Core Turbo Frequency: 5.4 GHz
High-Performance Core Base Frequency: 3 GHz
Efficient Core Turbo Frequency: 4.3 GHz
Efficient Core Base Frequency: 2.2 GHz
Processor Cache: 36 MB
Maximum Internal Memory Supported by the Processor: 128 GB
Memory Types Supported by the Processor: DDR4-SDRAM, DDR5-SDRAM
Memory Channels: Dual Channel
Maximum Memory Bandwidth: 89.6 GB/s

What would be your opinion between the two CPUs and there's any suggestion in between ? (i9-13900K ~~ 650 euros, i7-9800X ~~ 350 euros)

Thank you so much, and I'm sorry for bothering you, I'm just a bit desperate due to having little time to choose the PC for the research group :') .

[flotus1]

Hi there, I moved these posts to their own dedicated thread. Feel free to adjust the thread title if mine is too generic.

Now, with the introduction of DDR5, these older quad-channel HEDT platforms like X299 heve been made obsolete IMO.
With a modern desktop CPU, you get at least the same all-core performance, with significantly higher single-core performance. So I'd say X299 is not an option.

If you want to mix things up from the I9-13900k, I see two options:
1) I7-13700k/I7-14700k: same amount of p-cores as the I9-13900k, at slightly lower frequency and cache size. A good trade-off if you want to save some money. Using faster RAM has a much greater impact on performance. I'd recommend something in the DDR5-6400 CL32 range. Unless you need 128GB of RAM, in which case memory transfer rates would need to be dialed back a litle.
2) For more performance, look at the Xeon-W 2400 series. They offer quad-channel DDR5, and the cores are pretty much the same as the P-cores in a 12th gen desktop chip from Intel.
It comes at a cost though: The 12-core Intel Xeon w5-2455X is ~1250€ retail, and motherboards start at 850€. E.g. ASUS Pro WS W790-Ace. It should still fit into the budget if you are only paying for parts. Also has the benefit error correction on the RAM, in case that's important to you.

[newcomer_123]

Hello Alex,

To start, THANK YOU SO MUCH, I learned a lot by seing your thread and comments.
I'm thankful for all your help and your options, now I understand the topic a lot better.
Unfortunately it seems that my country doesn't sell a lot of these better equipment (even for example, Xeon-W 2400 series), so I'll have to go with I9-13900K for 128GB of RAM, probably the best I'm going to get in the market for my price range. Because
after this the only products that are sold are really High-End like 5k - 6k processors.

Thank you so much for your help, and I'd like to resume what I learned with you:
- equipment should all be compatible;
- generally as CFD simulations require a lot of parallelization, Quad-channels are superior to Dual-channels as far as CPU goes.
- but new technology related to RAM memories can help to mitigate the lack of performance of dual-channel CPU in case it's not possible for the user to buy a quad-channel with the same RAM technology.