Sounds to me like the computer is not what we call 'posting'
Just wondering b/c you didn't mention...what Memory did you use in it?
Make sure the memory is seated properly, if your using 4 sticks remove 2 of them and make sure you leave the two in channel 0. Then see if it posts and go from there. Also that motherboard has integrated graphics as well, so you might try removing your other card just to check if it will post using the on-board one.
It would be kind of odd if its the memory since usually you will get a series of beeps upon turning it on... so check the graphics card first I'd say and then check the memory.
try it and post back here b/c there are lots of reasons for a computer not to post.
PC Troubleshooting Procedure List
^^ look at that list under new motherboard won't power up for further ideas.