9400 GT Dual Display Issues

I bought a Geforce 9400GT 512 MB card to get dual displays up and running on my WinXP machine. I'm trying to run a pair of Dell E190's, both of which I know work fine normally. I've plugged one into the 9400's VGA port, and the other into the 9400's DVI port via VGA-DVI adapter.

Windows and nVidia's software recognize both monitors and allow me to set up dual displays, but the monitor plugged into VGA port is not getting any signal at all. All of my drivers are up-to-date. I've been fighting with this for two days now, so any help would be very much appreciated. Thanks!