My system resolution problem

Hi Friends

Im using Windows XP 32 bit, I have MSI N275GTX TWIN FROZR OC edition with 19 inch LCD widescreen. and the maximum resolution of my LCD is 1440x900. Today, after when I turn on my computer system, the resolution of my LCD is not accurate. From NVidia control panel and from display properties, the 1440x900 resolution is not there but all resolution are there. I have used several display drivers for GTX 275 but still the same problem.

Please help me and tell that Is this the GPU problem and Im getting the same problem Linux operating system also.

My control panel display did not have an option for 1440X900 when I first used the monitor. I believe I set a game to that resolution(NR2003) and when I went back to into control panel there was option for 1440x900 available at that time. Not sure why, but it was there. I did not download a single driver. If that helps any1 out great. I don't know why it did it.