Resolution Issue.

Hello all,
I have a Samsung SyncMaster 940bw that I have connected to my intergrated graphics card, a Geforce 8300 (the motherboard is the Asus M3n78-Pro). The monitor itself pops up a box asking for a resolution of 1440x900 with a 60Hz refresh rate. However that resolution isn't listed in the display settings, I'm using Windows 7 64bit. I have read online that people are saying to correct this issue create a custom resolution in the Nvidia control panel and to have the monitor use that, however the control panel tells me that my monitor does not support the 1440x900 resolution. I have been working on this for about 3 weeks now. Any help is greatly appreciated.