memory types

[HoustonsProblem]

Hello,
I am looking at upgrading the RAM in my PC and stumbled upon ECC dimm modules. Both my motherboard (B550 chipset) and my CPU (3900x) support ECC, however the different types of ecc memory are confusing me (i.e. LRdimm, Udimm, etc) 
Mainly I'm just curious if these are interchangeable names, and if they should work fine.
speed of the memory isn't a huge deal since I usually do a small overclock (usually an extra 200-300mhz and 0.1-0.2 volts)
The main reason I'm considering ECC is that its much cheaper than normal desktop DDR4, especially in the capacities I'm looking for (64gb in a 32x2 kit)

[Electronics Wizardy]

Only udimms will work with your system. 

 

Generally the cheap stuff is rdimms, and that won't work in your system.

[RONOTHAN##]

2 minutes ago, Tech1diot said:

Mainly I'm just curious if these are interchangeable names, and if they should work fine.

They're not. Ryzen chips only work with UDIMMs, or unbuffered memory, and unfortunately when you're looking at ECC this stuff is usually significantly more expensive than non-ECC memory that will work or the ECC RDIMMs that won't work on your platform.