If you get your Desktop computer assembled or custom made, here is the configuration that works best for a Graphics Designer.
CPU: Preferably Intel i5 or i7 Processor
Motherboard: get a motherboard that supports 32GB or more Ram and SATA 3.0 and 2TB-4TB HDD
GPU: Prefer NVIDIA instead of a powerful graphics card
Monitors: IPS monitor with a Matte Finish
OS: Best option is Mac OS which can be used on a custom built PC.