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Ryzen Threadripper PRO 3945wx Or xeon

I'm on a budget and looking forward to build a Workstation exclusive for Ansys Mechanical, Explict Dynamics, Ansys ACP (composite modeling & Analysis) and 3d modeling using Inventor and Solidworks. [No CFD at all]

Ansys ACP usually used to much computation power due to too much details.

Newer Threadripper PRO 3945wx has 8x channels memory 12x cores and excellent core clock speeds with 64 MB of L3 cache.
I Will be installing 64Gb (8x8Gbs) of RAM, 512 GB M.2, 2TB HDD and some cheaper Graphics card.
Is it a good build for my use or I have to go for Xeon processors

First things first: don't buy Threadripper Pro. Especially not the SKUs with less than 32 cores.
It is unknown if they have enough compute dies enabled to benefit from their 8-channel memory interface. Judging by the amount of L3 cache, they don't.
Speaking more generally, AMD made their Threadripper Pro lineup obsolete when they launched 3rd gen Epyc CPUs. If you want to go with AMD, get a 7313p or 7443p.

Intels Ice-Lake CPUs should also be a good choice. Since they have a plethora of different options, we should first find out how many cores you want/need and how much you are willing to spend on the CPU.

Quote:

Originally Posted by flotus1 (Post 807838)

First things first: don't buy Threadripper Pro. Especially not the SKUs with less than 32 cores.
If you want to go with AMD, get a 7313p or 7443p.

Intels Ice-Lake CPUs should also be a good choice. Since they have a plethora of different options, we should first find out how many cores you want/need and how much you are willing to spend on the CPU.

I would start with 74F3 (with 256M L3), 128M 7003 might be even slower than 7002 with doubled L3 at similar price.

According to the good improvement from 7542 to 7532 posted in the steaky thread, and results by
https://openbenchmarking.org/test/pt...26f7a1#metrics

, it seems that the memory bandwidth depends closely on the size of L3, for both 7002 and 7003.

Icelake Xeon might be another story, review by Anandtech shows quite large advantage over 7003 in raw bandwith, however openbenchmarking results are not so great. I just booked one (2*6336Y) from lenovo, however it would take at least one month for manufacture and assembly...

128MB L3 cache on Zen3 means at least 4 compute dies active. Which is enough to saturate the read bandwidth of all 8 memory channels, same as Zen2.
The 74F3 is no doubt a great CPU. But the price increase compared to Zen3 Epyc with 128MB L3 is extremely steep. I went with a recommendation that is roughly the same price bracket as OPs original plan.
The results in the link you posted seem to be all over the place. Maybe not the best resource to compare CPUs.
If I recall correctly, Ice lake Xeons get their memory bandwidth advantage in the stream benchmark from hardware-level implementation of streaming stores. That's definitely a neat feature, but we have yet to see how this translates to real-world performance improvements.

Quote:

Originally Posted by flotus1 (Post 807853)

128MB L3 cache on Zen3 means at least 4 compute dies active. Which is enough to saturate the bandwidth of all 8 memory channels.
The 73F3 is no doubt a great CPU. But at pretty much triple the price of a 7313p, te price increase is extremely steep. Not to mention that the 74F3 with more cores is cheaper.

I didn't realize that 74F3 triples the price of 7313p, in this case 7313 is much more cost effective.

However in terms of L3 reliance of bandwidth, it seems that increase from 128 to 256MB does make a difference, according to https://openbenchmarking.org/test/pt...26f7a1#metrics, that's around 30% improvement, comparing 7443 with 74F3.

Currently this is the only source and so far no post of CFD benchmark on 7003, but for 7002 I think it is safe to say that bigger L3 really matters, according to 7532 (256M) of

Quote:

Originally Posted by Novel (Post 788268)

cores time (s) speedup
1 677,34 1,00
2 363,04 1,87
4 161,42 4,20
6 101,82 6,65
8 77,16 8,78
12 52,28 12,96
16 39,4 17,19
20 32,01 21,16
24 27,31 24,80
28 24,15 28,05
32 21,53 31,46
36 21,32 31,77
40 20,46 33,11
44 18,99 35,67
48 18,12 37,38
52 17,45 38,82
56 17,06 39,70
60 16,5 41,05
64 15,91 42,57

and 7542 (128M) of

Quote:

Originally Posted by Novel (Post 788268)

Code:

# cores   Wall time (s):

------------------------

1 724.16

2 346.29

4 165.72

6 107.43

8 82.14

12 55.02

16 41.32

20 37.03

24 33.5

32 26.79

48 22.99

64 21.5

Quote:

Originally Posted by flotus1 (Post 807838)

First things first: don't buy Threadripper Pro.

Speaking more generally, AMD made their Threadripper Pro lineup obsolete when they launched 3rd gen Epyc CPUs. If you want to go with AMD, get a 7313p or 7443p.

Intels Ice-Lake CPUs should also be a good choice. Since they have a plethora of different options, we should first find out how many cores you want/need and how much you are willing to spend on the CPU.

Thanks for a quick reply. I'm really thankful for you time and effort to solve my problem

1. I have $5000 for for workstation.

2. I think 7443p would be a good choice. 24 cores may be enough for me. I'm a noob to this FEM world. where to get it ordered.

3. Can I get better performance/dollar with another EPYC (Milan or Rome) or Intel Xeon CPU keeping my budget well within $5000.

Quote:

2. I think 7443p would be a good choice. 24 cores may be enough for me. I'm a noob to this FEM world. where to get it ordered.

Availability of these CPUs depends on which part of the world you try to get them. Still seems to be pretty hard to get in North America, but they are readily available in Europe: https://geizhals.eu/amd-epyc-7443p-1...loc=uk&hloc=eu

From Intels latest generation of CPUs, the 6312U seems to be the closest match in terms of core count and price.

As far as performance goes, it's really hard to tell at this point. Both CPUs are quite new, and I haven't seen a whole lot of relevant benchmarks for them.
My personal bias would tend towards AMD. Users report it clocking close to 4GHz with all cores active. And it has the larger L3 caches. Intel on the other hand has support for AVX-512, and potentially higher memory bandwidth for codes that weren't compiled with streaming stores.
I don't think you would go seriously wrong with either of these CPUs. So if one isn't available, just pick the other.