> "800–2133 Mbps" according to page 9 of the document tlosm mentions.

That's the official JEDEC spec numbers for DDR3.

> The documentation you've pointed to mentions a slightly slower max "800–1866 Mbps"
> for the T10xx.

My first linked document (which is the same as linked by Spectre660) shows DDR3 spec, while my second linked document shows DDR3L spec instead, hence the difference in max value.

> So he may have a point

I don't think so.