Except Espressif SPIRAM, Lyontek's psRAM chips also works with ESP32. I have also tested IPUS IPS6404 SPIRAM (the 3.3V version available at Electrodragon and it works without issues. Hi loboris, I also add more Rams for ESP32 Wroom 32D by using IPUS IPS6404, what you recommend. But it doesn't work....