So I recently decided rather than make a new PC seperate from my school one I should just make a PC good enough for school and gaming. It's an OEM PC from HP and so far from what is listed on the box it has:

A core i3 4160 dual core with intel HD graphics and 12GB on ram on 2 seperate sticks.

The problem is it has a pre built motherboard with HP plastered all over it. It has a PCIe 16x slot and 2 other PCIe 1x slots. I don't know whether or not its 3.0 or 2.0 though, most people say it doesn't matter. The CPU has a LGA 1150 socket so I figured any CPU would work with as long it has the same socket. My dad who use to work at AMD and Intel now works at Samsung has been a PC build enthuisist for a long time so he actually sent me a Xeon e3 1231 v3 cpu when he heard I was struggling putting money forward for a new PC. He told me not to go the AMD route because their CPUs are mixed with new and old technology so they are weaker per core and won't last me as long. I want to upgrade the RAM and my CPU but I have no idea if itwill even work even though it appears to be a normal motherboard.

This is why console gaming still exists.

Anyway, what is your actual question? I didn't seem to find one?

I have a PS3, PS4, and a Wii U :p

But I wanted to know if I could simply swap out the CPU and RAM on my PC even though it an OEM HP Computer. The CPU is the same socket that's currently in my PC.

Why exactly would you need to upgrade the ram? 12 GB's is plenty. The CPU your dad sent you should work as long as your motherboard supports LGA 1150. You probably need a GPU upgrade, and since your PC is an OEM HP then it is likely the power supply won't support something great so you'll probably want to upgrade the power supply. What is your case size?

Make sure you update the bios with your i3 and you have a dedicated card before putting the Xeon in though (Xeon's don't have an IGP.)

Check with the manufacturer (HP) whether or not the bios supports Xeon processors. Usually they do, but they require an update to the bios. 

Yea I forgot to mention I have a GPU and PSU being shipped to me in about 2 weeks or so.

Buy a laptop.

I want to upgrade it because it's slower 1333mhz ram. I thought 1600mhz was pretty standard or does that not real impact gaming.

You're more than fine with RAM, that Xeon is nice bump from i3, all you need is some nice GPU and you're set.

Good, so all you really need to do now is check whether or not the bios supports server CPU's (Xeons.) HP should have a list of supported CPU's or you can check the chipset information.