Windows can not boot up with new video card

Hello,

I recently purchased a new video card geforce gt 240 DDR3 since my old one died a few weeks ago. The PC I have is a Dell Inspiron 530 purchased on Dec 2007 with a windows vista system. When I inserted the new card in and plug the video cable to the new card, I can get into the system with a pretty bad resolution. Then I installed the driver from the cd and was asked to reboot the system. Then the problem poped up: I can see the boot up screen and even the screen of the process bar with windows vista, but then it showed me a blank or black screen and wouldnt show me the welcome screen to input my password. But I can still get into the safe mode with a video.
I have been searching around for a solution and tried several things:

First, I went to the safe mode and uninstalled the video card driver; then i rebooted and the system can load, just like I didn't install the driver; then in the system windows automatically installed the driver for the new card. I checked the device manager, it can recognize GT 240, but with an attention mark says: Code 1, the device is not configured correctly. Then I was asked to reboot the system. The same problem happened when I rebooted and I could not get into the system just like before.

Second, i got to know that somebody recommended to change the PCIe settings in the BIOS. I then got into the bios (version 1.0.7) but I could not find the PCIe settings. There were only a few settings available in the bios:

The first display: PCI or PCIe : I tried both
Memory size: 8Mb
Mode: Fixed or DVMB: I tried both
Max Memory size: 256MB

I do not know what to do next. Can someone help me?

Thanks a lot!