Re: Upgrades for my dell Inspiron 3520
Laptops are very limited as to what you can upgrade, most of the time you can add more memory or a better hard drive but that's about it. On rare occasions you might be able to upgrade the processor and graphics, if it's not soldered onto the mother board. Most of the time manufacture's discourage that and do not offer any support as to what processors are compatible, even if it's not soldered.
You already state you have 4gb's of memory, so you need to check the specs of your laptop to see if could even handle more than 4gb's