Help with new video card

[titeo]

I just installed a new video card ATI X1600 Pro 512MB PCIe (with 1 VGA input and 1 DVI input) into my DELL Dimension E510 Windows XP SP3 and download the driver for this video card and installed it sucessfully. Then I disable the integrated onboad video card and reboot the PC to use the new card. Windows boot up OK but after that the monitor display blank and even when I tried "Ctrl-Alt-Del" to access to the task bar or device manager to see what happened but nothing was displayed. I restarted the PC and press F12 to setup the system and selected the add-in video card, saved it and restarted the PC again but the monitor still displayed blank after Windows XP boot up. I tried to connect to the DVI input to a different monitor to check if the display was defaulted as the primary display or not but the situation was the same. I tried to reboot the PC and press F12 again to setup the old video card back and connected back to the old card input but the system sent a message that I should connect to the add-on video card. Please let me know what the problem is or how I can get the display with either new or old card. Thanks in advance.

 

[titeo]

Further info

I tried to connect the remaing video output to a second monitor to see if the screen happened to be display there but it showed "no signal". Then I moved the cable back to the old one, there was a message telling that the cable should connect to the card so I could not go back to the old one unless I remove the new one. Still struggle with that for several hours and could not figure out the problem. Look like Windows did not recognize the new video card. Anyone has any idea, I appreciate it.