IBM PS/2. 2 Mb. RAM MEMORY for model 80. IBM OEM W/WARRANTY. | eBay
How to use 4Mb external PSRAM on ESP32 WROVER module.? - ESP32 Forum
Greg on Twitter: "Soldered up a quick board to test these Chinese PSRAM ICs. 64Mbit of PSRAM (DRAM with internal self-refresh) in a QSPI/SPI SO8 package! https://t.co/hQ3ZfyUX0U" / Twitter