Going for a gamer type computer is a good bet. Big screen - check. High end processor - check. Lots of RAM (>8GB) - check. Big edit: FAST Harddrive (SSD) - check.
Graphics cards can speed up some software for some processing algorithms. My experience with GIMP is that it is mostly a CPU intensive program. Photoshop might have some graphics card based processing algorithms, but then again, they may not be the ones that are often used for astrophotography processing, and the ones we do use a lot, have not been programmed to use the GPU.
Edited by ericthemantis, 23 August 2019 - 03:26 PM.