I thought I would make this post, because I was unable to reply to the archived posts about this model. I was able to get my hands on one of these back in 2017. The Iconia 6120 it's still a very unique animal in the world of laptops, because it had two touch screens, and the lower one used a touch screen keyboard and Jog wheel. It came as an Intel i5. I no longer have it because I was able to upgrade it and sell it for a higher price. It certainly did have its usefulness at the time, but not without limitations.
After looking at the questions in the archives, I can give you my answers to those questions based upon my own personal experience with my Iconia 6120 before I sold it.
First of all, I did successfully upgrade my Iconia to Windows 10, that was not a problem. What was a problem, is that Windows 10 had its own version of the touch screen system embedded into it's operating system, whereas the Iconia 6120 had its own program or system for the touch screens embedded into its own software, and the two were not able to operate together existing at once. Through a lot of work, I was able to disable the Windows 10 version of the touchscreen system, and just use the Acer program.
Concerning upgrading the Iconia 6120, I was very easily able to upgrade the CPU to an i7. I had to be very careful, and make sure I chose and I 7 very close to the original I-5 specs, that also included on board Graphics processing. The Acer system bios had the memory locked down to eight gigabytes. I was able to research and find on one of the computer geek sites at the time, one of the moderators of that site had an Iconia 6120 as well, and had made an unlocked version of the bios that allowed for installation of a 16GB stick of memory. I never got that far with my machine, so I never switched out the by us or replace the memory. Just relaying that that information is out there