Monitor won't display with new graphics card

[hhghp1305]

Hi , I decided to buy a new AMD HD 7770 to replace my old 4650 card, so before i actually buy it, i borrowed a friend his ASUS 6770 to see if it can work on my old computer. And after i installed the 6670 and started the computer, i heard a long beep, and my monitor wouldn't start, it was in save mode, but i could hear the background music when window starts and when i pressed the power button to shut down, i could also hear the window music when shutting down. When i changed it back to my old 4650 card, it starts normally with a short beep. I used VGA port and haven't tried DVI or HDMI yet, but i don't think that's the problem. My specs :
CPU Intel Core 2 Duo E6550 2.33 Ghz
MB: Gigabyte GA EP45-UD3LR
PSU: AC Bel CE2 450W
4 GB RAM
500 GB HDD
Is this because of the PSU ? But I think my PSU is enough to handle this card

 

[markwp]

Did you plug in the 6 pin connector to the 6770?

 

[hhghp1305]

Did you plug in the 6 pin connector to the 6770?

So it turned out that's the exact problem, because my old card doesn't need to plug in a 6 pin connector, so i didn't know, can't believe i was so dumb, thanks a lot for pointing that out, save me a lot of time there.

 

[markwp]

No problem. Glad you got it going.