C++ Slow Compile Time

Hi, I am having problems with compiling code. It is taking me between 2 and 3 minutes to compile my code which is for obvious reasons unacceptable for my workflow.
The intellisence also takes too long to load.
Also, UE4 takes a very long time to launch, can’t say exactly how long but roughly 3-5 minutes.
I have tried all of the “quick fixes” that I have come across with no success.
My computer isn’t the best so I am planning on upgrading some hardware to solve the issue.
What do I need to upgrade to fix this issue?
Thanks.

My computer specs:
Intel i5 3470 CPU
ASUS Motherboard, model: P8H61-MX USB3
8Gb RAM
NVIDIA GeForce GTX 660
1TB HDD