If it's SATA, then it should probably work. I believe the Dahua DVRs take SATA hard drives. I ordered my first Dahua and it's coming but all the other DVRs I've installed used SATA. I don't think any machines now use EIDE anymore unless it's really old or a PC.
That DVR has two sata connectors, but everywhere is writed, that works with 3,5" sata hdd. I want to use 2,5" notebook sata hdd. Sata and power connectors are the same.