Hardware for rendering JPG 4k Videos

Been having a hard time finding reliable information on this subject. When I export a video sequence in Unreal using the JPG exporter, what hardware is mainly being used? I want to produce 4k videos but Unreal is crashing on me about with about 10 seconds of footage. Keep in mind that the scene which I am “rendering” is very high poly. Here is an example.

Exporting this video was a nightmare and took me a few tries just to get 40 seconds of footage. I want to render out out these videos swiftly and without hassle and prepared to make the investment. Any information would be super helpful.

My current PC setup is:

Operating System - Windows 10 Home 64-bit
CPU Intel Core i7 4790 @ 3.60GHz 36 °C
Haswell 22nm Technology
RAM 32.0GB Dual-Channel DDR3 @ 979MHz (11-11-11-27)
Motherboard ASUSTeK COMPUTER INC. Z97-A-USB31 (SOCKET 1150) 26 °C
Graphics 4095MB NVIDIA GeForce GTX 970 (ASUStek Computer Inc) 30 °C
232GB Samsung SSD 850 EVO 250GB (SSD) 35 °C
3726GB Seagate ST4000DM000-1F2168 (SATA) 28 °C
931GB Western Digital WD My Passport 0820 USB Device (USB (SATA)) 28 °C