Second monitor detected but not receiving signal?

I'm at my wit's end trying to figure this one out. I have an ATI Radeon X1600 (DMS-59 connector with DMS-59 to dual-DVI adapter). I'm trying to get dual monitors working properly. So far, I've tried a few different Debian-based distributions. The only one I can get to properly display on both monitors is Backtrack 5 R3. The problem: both monitors are detected by xrandr, and all settings look exactly the same. However, one monitor will not come out of standby. It doesn't appear to ever receive a signal. I've even changed the display layout in the System Settings. The screen size is correct, and the positioning is correct. I can even move the mouse to the second monitor, but it just stays in standby mode. Any ideas? ***EDIT***
Output of xrandr follows:
~# xrandr Screen 0: minimum 320 x 200, current 2880 x 900, maximum 8192 x 8192 DVI-0 connected 1440x900+1440+0 (normal left inverted right x axis y axis) 408mm x 255mm 1440x900 59.9*+ 75.0 1280x1024 75.0 60.0 1280x960 60.0 1366x768 60.0 1360x768 60.0 1280x800 74.9 59.9 1152x864 75.0 1280x768 74.9 60.0 1024x768 75.1 70.1 60.0 1024x576 60.0 832x624 74.6 800x600 72.2 75.0 60.3 56.2 848x480 60.0 640x480 72.8 75.0 66.7 60.0 720x400 70.1 S-video disconnected (normal left inverted right x axis y axis) DVI-1 connected 1440x900+0+0 (normal left inverted right x axis y axis) 408mm x 255mm 1440x900 59.9*+ 75.0 1280x1024 75.0 60.0 1280x960 60.0 1366x768 60.0 1360x768 60.0 1280x800 74.9 59.8 1152x864 75.0 1280x768 74.9 59.9 1024x768 75.1 70.1 60.0 1024x576 60.0 832x624 74.6 800x600 72.2 75.0 60.3 56.2 848x480 60.0 640x480 72.8 75.0 66.7 60.0 720x400 70.1 And the monitor is a Dell SE198WFPv.