better or worse battery life with xp ?

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.

 

Vista does have far a far superior power management system compared to XP. I've been able to get 5+ hours on my tablet with Vista. Vista has more advanced configuration options for what to give power too while on the battery.

 

hmm thnx. i guess i am not going to install xp then. i am getting about 4 and a half hours on display level 12 and other reasonable settings. Is there some bad aspect to underclocking the cpu? what is a reasonable percentage i can underclock it to? i am a student . i just need to use onenote , word , power point and opera most of the time ( mostly at the same time).

 

I would just use the power saver profile and maybe up the brightness a bit to make the screen more readable. I use my tablet for the same stuff and I'm quite impressed with Vista's power management.

 

I have both installed, and I get much better battery life in vista

 

The power plan options in Vista are nothing but cosmetic. Pretty useless. But I think Vista has some slightly better C3-Sleep-State management and usually consumes marginally less power if you deactivate some of its power consuming services.
But there is some weird behavior under the hood. We have discussed this in German Thinkpad forum for a while. There seems to be two groups of Thinkpad users: some get ~6h with Vista, better than XP, and some only get 4h. All get 5-6h with XP. So there seems to be some difference in Vista pre-configuration. But we where not able to pin this down, even after couple of months of discussion. Unfortunately my x61t belongs to the latter group :-(

NHC does not work on the x61t. The new beta of RMclock does. But effects are reported to be minimal for the LV CPU. If you have a normal CPU you can save significant power.

 

I concur with this, but I'll add in: NHC won't work on any Santa Rosa-platform (or later) system until the developer includes support.

 

The Sleep support in Vista is better than XP. Vista sleep consumes less power and you will not get the problem of programs preventing the computer from entering sleep mode. Also Vista requires less time to return from sleep.

 

Are you sure?
I cannot imagine differences in sleep power consumption. And XP starts whithin 2s on my old and slower laptop, my x61t needs 8s to resume from Ram which is unacceptable slow. Xubuntu resumes in 4s for comparison (natively. This can be further tweaked).
BTW, neither my old laptop nor my desktop, both running XP, have any problem entering sleep or hibernation. But x61t from time to time has sleep/resume issues under Vista.

 

Power management under Vista is a lot better than XP. There are more options in Advanced mode and there's also hybrid sleep. Also the Lenovo stretch mode I don't think is available in XP.