Maybe some day I'll find a 570/580 card with 2250 ram... but today is not the day. I've noticed the mfg. only put 2000 ram in all the 4gb cards, they save it all for the 8gb cards it seems??
I think none uses 2250 yet...RX570s and 4GB RX580s use 1750, and RX580/8GB use 2000
8GB cards with Hynix go to 2250.
For example this Sapphire Nitro+ Limited Edition RX580-8GB has 2250 Hynix:
https://www.techpowerup.com/vgabios/191263/sapphire-rx580-8192-170320-1
No, they have STRAPS for 2250, doesn't mean chips inside are 2250 rated...my RX560 Gigabyte cards have 2250 straps too,
card works at 1750, and its already factory OC-ed because chips on board are 1500MHz ones
Even link you posted clearly states "Memory Clock: 2000 MHz"