I went away from a 5.1 system and use just stereo for a few years now and i watch everything on my pc but dont really miss the surround. Most of the time I use a good set of headphones and an O2 usb amp and dac combo from mayflower electronics if im sitting at the desk.
I got this kit for a new 3900x build. Have not got to test it yet but im hoping for the best.
https://www.gskill.com/product/165/326/1562839044/F4-3600C14D-16GTZNTrident-Z-NeoDDR4-3600MHz-CL14-15-15-35-1.40V16GB-(2x8GB)
I got one of these a few years ago and they are good. Sometimes you just have to get down with some qtips and isopropyl alcohol.
https://www.newegg.com/white-metrovac-datavac-electric-duster/p/N82E16896367002?Description=electric%20duster&cm_re=electric_duster-_-96-367-002-_-Product
I have had good luck with Noctua, Corsair, and Noiseblocker fans in a few builds. Used to use some Scythe slip stream fans but i dont know if they still make them.