All the Dell computers I've had have the user guide on the hard drive, but in case yours doesn't, you can download it from the Dell web site. You can also go to the Crucial web site, download their analysis tool and run it. It will analyze your system and tell you what your options are regarding RAM.
Dell 3847 I5, Windows 8.1 64 bit.
Had reason to open my case, and noticed it only has 1 RAM slot. Does that mean 8GB is my limit?