Best Specs for DTP PC?

Hello FM Community!

Hopefully you guys could provide me with some much needed advice.

We're looking at purchasing a new office PC, which would primarily be used as a dedicated PDF printing machine as the processes have been slowing down other applications on our current desktops (which are fairly lacking on processing power). I was aiming to custom build to get the most for the money, but I wanted to know whether a graphics card has much impact on DTP tasks and printing speed, or whether it's purely down to the processor & RAM.

Currently our PC's are pushing out a fairly large manual at 6+ hours..

But after printing the same manual in a couple of other environments, we got the following results

Environment 1 (office pc):           AMD A8-7600 Radeon R7, 10 Compute Cores 4C+6G @ 3.10GHz - 8gb RAM =  around 6 hours printing time

Environment 2 (laptop):               i7-4770K @ 3.5GHz - 16gb RAM = 25 minutes printing time.

Environment 3 (home PC):          i5-4310M @ 2.7GHz - 4gb RAM = 1 hour printing time.

Environment 4 (surface book):   i7-6600U @ 2.6GHz / 2.8GHz - 16gb RAM = 5-6 hours printing time.

We want to make sure that we aren't going to end up in the same position we are now with an insanely slow printing time - as often some change may need to be made to a manual post-printing and we end up losing another 6 hours.

We've put together the following parts, but any input would be very much appreciated (hopefully the link works)

https://uk.pcpartpicker.com/list/QfcL8K

Regards,

Aidan