Lack of other 4GB RAM alternatives for MP25x

[DMårt]

Due to the high cost of RAM. I wonder if ST have plans or other information about which 4GB RAM vendors fits MP25x products?

I know that ST have information about other RAM vendors on their wiki. Only one 4GB vendor is mention there.

I bought the 4GB RAM MT53E1G32D2FW-046 WT:C (single rank) from here when it cost 20 USD.

https://www.aliexpress.com/item/1005009146059053.html but its seems to only having the DDR density to 8bits (2 GB). Perhaps it was only a 2GB or MT53E1G32D2FW-046 WT:B (dual rank)

I'm still looking for other RAM vendors that can offer 4GB solutions for the MP25x. 

Question:

Can ST write a criteria what a RAM memory need to have to fit MP25x? Do the RAM need to follow a specific RAM standard? What do I need to know to know if the RAM memory fits the MP25x?

[PatrickF]

LPDDR4 dual rank need 4 x Chip Select (2 rank x 2 channels). The STM32MP25 have only one Chip Select per channel.
So, memory like MT53E1G32D2FW-046 WT:B are simply not supported as you cannot select the second rank.

There is no real rationale that dual rank are cheaper as you usually pay for Gbit (= silicon area). Maybe pricing difference is only due to weaker demand of this particular device.