no boot

Hello everyone. My dahua nvr stopped booting and doesn’t show video in monitor. Tried replugging HDD and nothing happens. So i was thinking on hard resetting, but don’t know how to do it. Picture of nvr’s inside

Greetings Everyone! I have recently acquired an used old DVR. Its an 8 channel analogue device. On the box it says IP Vision - nothing else. Hence, identifying this thing has become a great challenge, let aside the issue with the device. While trying too boot up it says "Embedded Net DVR" on...