Memory upgrade, need help

I am no expert when it comes to rendering but generally, when it comes to 3d you
benefit more from speed than Error Checking. Most ECC kits are slow by comparison
to standard RAM. That said, if render speed is less important than accuracy, ECC
could be a better option for you. Errors when rendering are rare but can happen.
Unlikely as they are, most recommend against ECC for small scale/personal render
stations. This is largely owing to cost however so if you can find a decent ECC
kit within your budget, It may be worth looking into. If all you want is performance
then getting the fastest kit your board supports (in that capacity) will serve
you better.

Looking at your board's QVL:

ECC: KSM26ED8/32ME (ECC) (Kingston)
The board supports up to 4 modules of this RAM type at 2666

Standard: CMW128GX4M4E3200C16 (Ver3.44) (corsair)
The board supports up to 4 modules at 3200

Your board's RAM QVL: https://www.asrock.com/mb/AMD/TRX40%20Creator/index.asp#Memory

Make sure to pay attention to the "DIMM Socket Support" column. It will tell you
how many modules are officially tested and known to work on your board. The 2
kits I suggested both support up to 4 modules, some faster kits only support 2.
Typically I don't recommend more than 4 modules on an HEDT system and 2 on a standard
system as it puts more strain on the memory controller and can limit XMP speeds.
It will work but you will often find yourself having to lower the XMP speed a
notch or 2 for stable booting and use.

If you have further questions you can open a support ticket with ASRock here:
http://event.asrock.com/tsd.asp

ASRock's support staff will be better equipped to give you more specific advice.

For assistance with your memory upgrade query, it's essential to consider several factors such as compatibility, capacity, and timing. Given your CPU and motherboard specifications, ensure the RAM you choose aligns with supported frequencies and https://aristavision.com/ form factors. Additionally, verifying the maximum memory capacity supported by your motherboard is crucial.