Is the docking station 6PPXT A00 a PRO3X or PRO2X?

Remember that whether or not the dock supports USB 3.0 depends upon whether the system has an Intel USB controller.  Older systems don't - or they have supplementary NEC/Renesas USB 3 controllers.  These won't run external dock USB 3.0 ports even if the dock supports them  -- you must have a newer system that has an Intel chipset that fully supports USB 3.0.

That means a Latitude 6230 or newer - 2012 or later.

Thank you for your reply. I know that the docking port model 6PPXT A00 does not have USB 3.0 regardless of what laptop I am using it with. I am wondering though if it was falsely advertised, but I cannot find any information that indicates if all PRO3X's have USB 3.0 or whether a 6PPXT A00 is a PRO3X or a PRO2X.

What model system are you connecting it to?  And what OS is running?

While I was planning to connect it to an E6420 (Windows 10), which it seems to turn out wouldn't support USB 3.0 anyway (only Ivy Bridge and later), that is collateral to my question. I can see clearly that what I received does not have USB 3.0. I am wondering if the model number 6PPXT A00 is in fact a PRO3X as it was advertised to be or a PRO2X regardless of whether I would have be able to use the USB 3.0 functionality.

6PPXT appears to be the USB 2.0 version, at least according to all but one description I've seen.