downloading more ram first
second i go download a couple more cpus and threads
then a couple titan xp's if i feel its too slow
downloading a few terabytes of ssd storage is simple and easy to do(would reccomend)
downloding a case is good so your dog can't get that sweet new ram you just downloaded
case fans are essential so i usually download them once i build my pc(though if you havnt would try that)
your motherboard usually is good enough not to download but just in case\
download a second cpu cooler to lower your temps
downloading a PSU is the most crucial part of a pc I have 9 in my current pc!
downloading rgb is last resort