Mining rig gives little speed increase

[LittleGrand]

Hello,

I am trying to crack my wpa2 password using password list.

I am using windows 10 with 20.4.2 amd drivers and 12 AMD rx570 cards

I run hashcat with:

      hashcat.exe -a 0 -m 2500 hashfile.hccapx realuniq.lst

It runs. The CPU is always 100% however the gpu's seem to do very little work, hopping around sometimes going to 100%.

The issue is that I can run the wordlist on my laptop in 1.5hours and it takes 1 hour on the mining rig.

Should this not be magnitudes faster?

Thanks