Acer monitor no working (no signal)

[squirrel15]

My acer P191w monitor isnt working. I finally build my computer and I turned it on for the very first time, I got the monitor from my brother who never had any problems with the monitor before. Here is my build:
Thermaltake V9 case
Gigabyte 890gx mobo
Gskill 1600 cas 7 ripjaws ram
Antec truepower 750w PSU
ATI (xfx) 5850 (stock not overclocked)
Seagate barracuda hard drive
LG cd dvd writer
AMD 955 BE CPU

My monitor turns on fine, it says "ACER" then it says "no signal" about 4 seconds later. Both the mobo and monitor have a DVI cables/ports. My computer turns on fine, all the fans and PSU works too. I looked all over the internet and have tried the power cool down with the monitor (unplugging monitor and holding down the power button), I've tried unplugging and blowing in the cables and making sure theres not bend wires or anything and plugged them back in and still nothing. Any ideas as to whats wrong and how I canfix it would help greatly. Thanks.

 

[DeathAbyss]

Do other monitors work with your computer? Isolate the problem, it might be your graphics card that isn't working.

 

[squirrel15]

Its not the monitor, I tried it on my friends laptop and it works fine. Its definitely the computer.