i searched this forum and couldn't find any relevant information regarding this issue. i was wondering if i install xp as a second operating system will the battery for my x61t last longer? i found on other websites that vista is better in power mangement and so batteries last longer in vista than xp. but those were for dell laptops. i don't know if it is applicable to x61. also is this program called NHC (notebook hardware control - http://www.pbus-167.com/nhc/nhc.htm#anchor_download ) useful? will this cause any problems to my system? thanks guys.