I recently transitioned my PC to a SFF case and have the remainder of the computer ready available as a great basis for a fairly modern gaming computer. It will have no problem playing most recent games at 4k/high settings at 60FPS with the proper CPU (AM4) and RAM (DDR4)
Included:
GPU: MSI RTX 3080 Seahawk (hybrid liquid cooled, radiator + dual fans)
Case: Fractal Design Meshify 2 Compact
CPU Cooler: Noctua NH-D15 dual-tower air cooler
Motherboard: MSI MPG X570 Gaming Plus (AM4)
PSU: EVGA G5 1000W ATX -or- EVGA 550W SFX
Wi-Fi card installed
Cooling: 4x case fans + 2x fans on the GPU radiator