Processor speed vs. battery life

[anubis]

To those of you who responded to my last post, thank you. Howerver, I am now considering buying a 15" powerbook, since my budget will allow me to, barely. My question is now, were I to get the 1.25 ghz version, how much does the higher processor speed affect the battery life? I know that the 15", in general, has a low battery life, but will the extra processor speed really reduce the time by a full hour, or will it only be a matter of minutes? Thank you!

 

[Padawan]

To those of you who responded to my last post, thank you. Howerver, I am now considering buying a 15" powerbook, since my budget will allow me to, barely. My question is now, were I to get the 1.25 ghz version, how much does the higher processor speed affect the battery life? I know that the 15", in general, has a low battery life, but will the extra processor speed really reduce the time by a full hour, or will it only be a matter of minutes? Thank you!

Apple claims a 30 minute difference between the two (5hrs vs. 4.5 hrs). The actual life and difference will obviously vary depending on a number of factors. For instance, even though Apple claims 6 hours for my iBook, I find that with my usage (full processor speed, Airport on, and HDD and screen never shutting off) I usually see around 3.5 - 4 hrs. Based on this, I wouldn't expect tremendous battery life out of a 15" PB with normal usage.