I have some uh … “Western Digital Internal/OEM 512GB SN530 WDC SDBPTPZ-512G-1012”
I pulled these from a Dell OEM, and I peeled back the sticker on one of them, there’s a small package of DRAM.
Yeah it’s only 512, but it’s also only 1-sided.
yeah SATA can be quite easily saturated, with a max speed of about 550MB/s. Most drives I have can pretty consistently reach speeds over that, on mixed data. On PCIe3/4 it’s not close.
Also check this out
[M.2 2230 ONLY] SSD Survey - Framework Laptop 16 DIY