Today I built a system from scratch. Over several hours, I got everything seated, screwed in, plugged in, and cabled. I connect the monitor by DVI, turn it on... and nothing happens. Fans spin up, LEDs turn on, I can hear the hard drive doing its thing, but the monitor obstinately keeps its power light orange. I checked the monitor by VGA to my laptop - it is a working monitor. I cabled the VGA to a VGA-to-DVI adaptor and plugged that into the card - still no signal.
So, we know it's not the monitor, and it's not the connector.
How can I figure out what actually is causing the problem, and then fix it?
Video card is a GIGABYTE GV-R577SO-1GD Radeon HD 5770 1GB.
Re-check your power and data cable connections to be sure they are properly seated. Re-check that the 4/8 pin power lead to the CPU is connected.
Try with the onboard video and see if that works. Is your power supply powerful enough? Did you plug the psu into the card?