Building high end desktop advice?

[SLP Firehawk]

Hello to all the great and knowledgeable people.
I determined I needed one more threadripper desktop but unfortunately AMD discontinued the 3rd gen threadripper and abandoned the platform so I could not order another one built as I did with my 3970X. The new versions are over $8k so I decided to buy the old discontinued parts and build it myself.
So, o'er the last 2 years I have scavenged around and gathered the new parts to build one.
I hate working on computers, especially expensive ones.
I have changed every part except for the Motherboard of PCs through the years starting with a 386, Pentium 2, P4, and i7 but I have never fully built one from the ground up (except for a very basic Pentium 3 long ago).
I am not looking forward to doing an expensive ground up build....so I am looking for advice from you veterans. 3rd gen Threadrippers are large CPUs and hot.
Below is the parts list of new parts I bought over the last 2 years planning for this. I intend this to be my last computer. Any advice is appreciated. Thank you in advance.

CPU
AMD socket sTRX4 Ryzen Threadripper 3990X 64-Core, 128-Thread Unlocked Desktop Processor

Motherboard ASUS Prime TRX40-Pro S
https://www.newegg.com/asus-prime-trx40-pro-s/p/N82E16813119260?Item=9SIASGMK867616

RAM
G.SKILL Trident Z Royal Series (Intel XMP) DDR4 RAM 256GB (8x32GB) 3200MT/s CL16-18-18-38 1.35V
https://www.amazon.com/dp/B088SR199B?ref=ppx_yo2ov_dt_b_fed_asin_title

case
Thermaltake Core V71 Tempered Glass Edition E-ATX Full Tower
Got the biggest most open one I could find for room and airflow

cpu cooler
https://www.icegiantcooling.com/products/prosiphon-elite
https://www.amazon.com/dp/B074ZLQZ8F?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1
I also bought a 360 AIO but I think this siphon unit will cool the big hot threadripper better and longer

graphics card
PNY NVIDIA GeForce RTX 4090 OC XLR8 Gaming VERTO EPIC-X RGB Triple Fan Graphics Card
https://www.bhphotovideo.com/c/product/1733322-REG/pny_vcg409024tfxxpb1_o_geforce_rtx_4090_24gb.html

Optical Drive
Pioneer BDR-S13UBK Internal Blu-ray Writer with M-DISC Support (Standard)
https://www.bhphotovideo.com/c/prod...r_s13ubk_internal_bd_dvd_cd_writer_black.html

Optical drive 2
ASUS BW-16D1HT Internal SATA 16X Blu-ray Disc Rewriter
https://www.bhphotovideo.com/c/product/1019271-REG/asus_bw_16d1ht_16x_blu_ray_disc.html

OS
Windows 10 Pro

PSU
SeaSonic Electronics 1000W FOCUS GX ATX 3.0 80 PLUS Gold Desktop Power Supply
https://www.bhphotovideo.com/c/prod...tx3_focus_gx_1000_focus_v3_gx_1000_1000w.html

Multiple Samsung NVME drives and SSD drives

One thing making me think I might be capable of doing this is I do have my Threadripper 3970X computer I bought from CyberpowerPC that I can use as a reference.

 

[uOpt]

Don't you want ECC memory (UDIMMs of course) with this?

With that much memory it might be cheaper to go with a platform with registered memory (the 32 GB ECC RDIMMs are dirt cheap).

 

[SLP Firehawk]

Don't you want ECC memory (UDIMMs of course) with this?

With that much memory it might be cheaper to go with a platform with registered memory (the 32 GB ECC RDIMMs are dirt cheap).

Thank you. I basically spec'd the parts from my older Threadripper I previously ordered from Cyberpower and it works great. Certified/approved memory was really scare back in 2020 so I got the above for my earlier machine and then later got another kit on sale after it became discontinued for this future build and saved it so that is why I have the above memory. ECC would be great if approved memory is available but I already have the above 256GB kit new in box...