Nvidia Tegra actualize but go very slow and sometimes does not respond , there is no call option to activate the 4 cores to improve performance , you have the same problem?
Can't find the core management options anywhere either.
When I updated mine I had a couple of problems. 1st it overheated like having a piece of ember in my hands and Google Play wasn't working properly, either freezing or giving me some problems with a "background data" option which I couldn't find at all. After rolling back Google Play services to a previous version I was able to update some stuff slowly one by one and even Google Play services themselves without problems now.
Right of the bat this update seemed to make the tablet a bit sluggier I'd say, mine at least. But now after getting over the stress with Google Play and all it's getting more fluid.
When I first updated every time I rebooted my tablet would optimize all my apps. Ended up doing a factory reset to solve the problem. No over heating tho
For me several factory resets not solved the problem, again overheating, lags, battery drain.
I've flashed back to 4.4.2 using SuperTool 2.7. Now TN7 work fine and no problems....