PC starts up but "No Signal" - I've tried everything

[serilex]

I have recently bought a new gaming rig. I ordered all the parts and built it just less than 2 hours ago. Now, when I press the power button the thing turns on, all the fans turn on and a green led on the motherboard turns on. However, when I connect this to my monitor, the monitor says "No Signal". I'm sure it isn't the monitor because I've plugged in my keyboard and the Caps Lock LED won't turn on. I am connecting my monitor to my computer with a HDMI cable thing, and my monitor has power. My graphics card is properly mounted, and my CPU and stock fan are fine. I cannot pin point the issue and I need some help. If you can provide any information as to what I should do, PLEASE reply. Thankyou very much.

 

[AMD Radeon]

by anything, you mean from this list?

step by step troubleshooting
http://www.tomshardware.com/forum/261145-31-perform-steps-posting-boot-video-problems

 

[serilex]

by anything, you mean from this list?

step by step troubleshooting
http://www.tomshardware.com/forum/261145-31-perform-steps-posting-boot-video-problems

Yes I tryed everything