Dell PowerEdge T610 Wont Boot up

I have a Dell PowerEdge t610 server running on ubuntu 14. I had setup this server as my internal mail server . A while back as i was upgrading i turn off thr server and plug out the RAM. Few days later i put back the RAMs in the server but now the server wont boot up.

Ive tried switching the RAMs with some of a working server, and still the T610 wont start up .

Upon plugging the power  the fans comes on for few seconds and the green light in the motherboard lights. The fans then stops rotating and everything goes silent.

The t610 server doesn't display anything on the monitor, The power button and the small screen on top of it doesn't display anything.

Please help

This server contains my organizations mails