No video - noob trying to troubleshoot

Please excuse my lack of knowledge.

I work at a school with a DVR HD SDI camera system with 16 cameras. The other day most of the video feeds went blank and said NO VIDEO. Some flicker in and out. A couple usually stay on.

The system is located in a server closet and we only access it remotely at the front desk. It is an independent system, meaning it is not installed on Windows or another OS. It has a monitor hooked to it which shows the feeds and allows the settings to be altered, which I can also do remotely because it is hooked up to our network.

The DVR came from A+ video in Taipai. (http://www.asmag.com/suppliers/productcontent.aspx?co=aplusvideo&id=17518) I have an old printed manual that says Version 4.0 on it. Otherwise there is no brand name anywhere, it just says DVR on the front. The cables look untouched, so I don't believe there is a hardware issue.

The software says Web Client. I found it on a site and it is called UMS client, but it is freeware and I don't see any updates: http://ums-multi-client.software.informer.com/download/

Here is a shot of the feeds with the No Video message:

http://screencast.com/t/vdnjXLuaN3mc

Here is an image of the Settings options:

http://screencast.com/t/fS4zqUE4

Please if you can, point me in a direction to troubleshoot this issue. I have restarted the machine several times with no change and do not know how to approach this problem.

I wrote to the company that made the machine but I don't have much hope. Thank you for any help you can offer!

That many cameras with NO VIDEO, that probably means that a power supply has died somewhere. Find out what is (was) powering the cameras that have gone black, and you will probably find the problem.

Thanks! I'll check out the power supply!

Thanks again. The power supply was broken and we are getting it fixed! Thank you!!