[Viktor_S]

The phone is like refreshes once in awhile. And while playing an RPG game it lags. I already uninstalled app and moved files. Is there a problem with the processor? My phone is a Samsung Galaxy J7 Core. Octa core. I installed an app to check my phone. It says only 4 cores are working the other cores says "stopped". Please help. Thanks!

[B. Diddy]

Welcome to Android Central! What do you mean the Facebook video stops midway -- does it freeze, or does it just dump you back to your Facebook wall? Are you using the app or the mobile site?

What do you mean that the phone refreshes once in a while? Are you talking about apps getting closed out of RAM, so that when you try to switch back to the app, it's as if it's starting up cold?

The J7 Core isn't a flagship phone -- it's a budget phone, so don't expect flagship performance when playing CPU-intensive games. As for the active cores -- are there any power-saving modes turned on? Does the phone come with any preinstalled Gaming Tools or Game Launcher app?