I downloaded the old Dell Nvidia drivers (as opposed to the ones Vista has been pushing out and installing, I had to hide this update), extracted the files and opened up the .inf file.
(Under [nv_SoftwareDeviceSettings] look for the line that starts with
HKR,, NV_Modes, %REG_MULTI_SZ%,) then I just added the resolution (which in my case was 1360x768) so it looked like this:
HKR,, NV_Modes, %REG_MULTI_SZ%, "{*}S 720x480 720x576=1;720x576=8032;SHV 1680x1050 2048x1536x32=1;1920x1200x32 1920x1440x8,16=1D;640x480 800x600 1024x768 1280x768 1280x800 1280x1024 1600x1200 1920x1200x8,16=3D;1920x1440x32=9;1920x1080=C01E;2048x1536x8,
16=D;1152x864 1360x768 1440x900=FFF;{40A-40F,42F}S 1920x1440x64 2048x1536x64=1F;640x480x64 800x600x64=1FC2;848x480x64 960x600x64=1FFF;1920x1200x64=2;{191-19E,400-42F,600-6E4}S 720x480x64 720x576x64 1680x1050x64=1;"
Then I installed this driver, rebooted and now it works (although only in dualview).