You can upgrade the RAM and drive without affecting the warranty.  That said, those are the only two components that are upgradeable. Be sure you disconnect the AC power and battery before  doing the upgrades.    
Hello all! I bought this computer last year after my Lenovo decided it didn't want to exist anymore. I have hardly used it as my other computer was working great until recently. Now I am moving all of my files and games to this computer. It's a bit slower, and the storage isn't all that great so I have plans to try and upgrade it. Not sure what kind of upgrades yet as I have to do more research, but I essentially want to make my computer have more storage and better handle my games and heavy programs so that the computer isn't laggy.  Long story short, I have a warranty on this computer for the next three years. Does me upgrading its ram, SSD, storage, or whatever I decide to change, void my warranty? I have seen parts that were far cheaper than what Dell is charging and while I would love to use Dell parts, I just can't afford the prices that they're asking for. 
Upgrading