Graphic card issue

Hello, I'm using windows 7 64 bit, my motherboard is Asus Striker 2 Formula. Yesterday I was on my pc in the morning , it was working fine. In the afternoon , i've tried to open it again, it wouldn't open , and bios did 4 beeps , 1 long and 3 short, I've searched it on the internet, and I found that it was because my graphics card ( ge force 9600 gt ) had an issue , it wasn't plugged in properly or it had dust in the gold fingers. I removed it and got it cleaned. Then I plugged it in again , my pc boots properly now , I can hear 1 beep but my monitor says no signal... The cooller under my graphic card is on , and I've tried to remove it and put it back several times . What should I do ?