Huge performance decrease on PTR


My system is ryzen 5 1600 3.9ghz OC, 16gb 3133mhz ram, GTX 1070. I always had stable 200fps locked on live, but when I login PTR to check out the ashe scoped fix, I saw my framerate went down to less than 120fps, my graphics setting in PTR is same as live, and tried restart the PTR, and it still has the same problem. Both my CPU and GPU has less than 50% usage when playing PTR.