NVR without POE

Hello, I currently run 4x8k HikVision cameras on my QNAP via QVR Pro and it is starting to cripple the NAS box. So I am starting to look at ta dedicated NVR or decent software I can run on a seperate PC.

Any ideas please? I don't need POE in the NVR as I have a 8 port netgear switch already up and running..

Cheers
Mark