This image says 384 KB of RAM: https://docs.espressif.com/projects/esp-dev-kits/en/latest/e...

It also says 320 KB of ROM, which seems low. Judging from the product name (DevKitC-1-N8R4) and their other products, it has 8 MB of flash.

Maybe 320KB is the size of the bootrom? Although I don't see why that would be worth mentioning.

If it's like the other ESP32s with PSRAM support then 2-8MB most likely. IIRC it is addressed in the same way as the NAND, so the more RAM the less NAND you can have.

Maybe not applicable for this new one, but that's my understanding for the S3/C5 models. (something like 16mb NAND and 8mb PSRAM)

onboard memory is limited. PSRAM is available