Using Pro Tools on a PC with Windows has always been a challenge. I started building PC's back around PT7 and 8-9.
It was always alot of reading in the duc.avid forum to see what others were running. Motherboard and CPU, brand
of RAM and the video card seem to be always important. I finally went to the "Dark Side" and have never looked back.
After doing the tweaks Avid suggests my Mac just runs. Yeah occasionally Pro Tools pukes but I am running
all SSD drives, on a 6 core 48GB Mac Pro Tower everyday 6-8 a day.