HP Pavilion dv9740us - Battery Problem

I have a HP Pavilion dv9740us Entertainment Notebook PC. I got it few months back from Newegg. I just installed Windows 7 and after that my notebook shows this error message "Consider Replace Your Battery". My notebook battery drains within 30-40 minutes. Can anyone help me to fix this problem? BTW my notebook was functioned normally and working pretty well with Windows Vista.

Thanks..

Welcome to the forums

Just so I understand this correctly... your laptop lasted for several hours when running Windows Vista, but now that Windows 7 is installed the batter only lasts for 30-40 mins?

Even an OS running the most demanding tasks shouldn't reduce the run time of a new laptop like that. It could be a hardware problem, so I would check out the warranty.