Gpu: Rx 480
CPU: intel i7 4770k
Installed RAM: 6 GB
System Model: alienware x51 r2
Windows 10 64 bit
If you need to know anything else, just ask.
I still need more to go on, it could be anything based on the information provided.
What PSU are you using? What are CPU/GPU temperatures? What is task manager showing when the lag spikes occur? Can you define lag spikes?