T400 with XP, how long battery life do you get?

Charge to 100%, shut down all running programs and all radios, then turn down brightness to 50% and let your computer idle. Alternatively you can calculate it by dividing 56.2 by the number watts the computer is drawing (you can use Mobilemeter to monitor this). And remember that 2,5 would be equal 2 hours and 30 minutes, he he.

If looking at runtime from 100% charge, then standardize the result with regard to the number of cells you've got:

• 4 cells multiply runtime by 1.51
• 6 cells multiply runtime by 1
• 9 cells multiply runtime by 0.663

This emulates everyone using a 6 cell battery. Ideally! you should be able to get almost 6.5hours, but from my and others experience this seems highly unrealistic. Lets see what the truth is, for XP users at least

 

Personally, around 3:30, not too impressive, and that's using a low power SSD.

 

I'm getting at least 8-9 hrs, on XP with the use of a 6 cell battery plus the 3 cell Ultrabay, running 100% discrete graphics and using Battery Stretch. Configured with the T9300, SSD, absolutely no plug in time during the day while at school. Taking notes, cruising the web when teachers are on tangents, exchanging info via flash drives, and powerpoint presentations. I've been absolutely amazed how long the unit runs on battery. My classmate's T61 with Vista Basic, 7200rpm HD, 6cell, runs out much faster than mine. I have not yet plugged in at school and I have lectures 9a-5p. Today I installed Dragon Speaking 10 to record lectures, I'm curious about the CPU load and the endurance of the battery for next weeks lectures. I'm excited to find out!! PS: Lenovo preloaded with XP

 

i get no more than 3 hours which is not impressive, 6 cell; realistic usage (no stretch or crap like that)

 

Hey Tommy, you forgot to follow my instructions. And ironically, so did I..yikes.

Anyways, your battery would equate to 5.5 hours with 6 cell batt, and with my 4 cell batt about 5 hours, using the settings I mentioned. I guess 5 hours with a 6 cell batt isn't bad, but it surely isn't fabulous either, remember this is running with wlan off and brightness at 50%.

 

50% brightness is a crime with LED

 

I get 2:00 hrs. on a 4 cell with 70% brightness and wifi with ati 3470, dvd drive autopoweroff and bluetooth off.
wish they had 6 cell flush for this model

 

Observations:
System: T400, 2GB ram, LED WXGA+, 4 CELL, 4in1 reader, discrete graphics.
Setup: Windows XP SP3 with only drivers installed, no programs running, set to max powersaving and using integrated graphics. Wifi off, wlan not plugged in.


32GB OCZ Flash SATA II SSD

Idle, 50% brightness 8.75w
Idle, 50% brightness, w wired network, 10.20w
Idle, Min brightness 8.5w
Idle, Max brightness Max 10.5W
Browsing folders 10w
Typing in Word 9.10w


160gb Hitachi hts5416 5400rpm (about 0.9W idle power usage, most 2.5" consume 1w)

Idle, 50% brightness 7.6w
Idle, 50% brightness, w wired network, 9.20w
Idle, Min brightness 7.25w
Idle, Max brightness Max 9.48W
Browsing folders 10.2w
Typing in Word 8.10w


Notes:
-Turning up brightness to 70% only increases power usage by 0.3w
-XP and VISTA has similar powerusage with both the SSD and HHD
-The SSD gives 13%! worse battery life when idling.
-The most powersaving SATA notebook harddrives manage 0.6W idling (Fujitsu MHX2300BT,SATA150/NCQ,120 GB, 8 M).
-The 4 cell batt states that it's 42Wh, which would in theory give me 5:30 using the HHD, realisticly I think 4:30 is possible with text editing.

http://www.tomshardware.com/charts/2...hmarks,25.html < for benchmarks of almost all recent 2.5" drives.

In summary: Just buy a huge 2.5" HHD, saves energy and you don't notice the speed difference much with "normal" use anyways.

 

Although the sample size is small, seems the majority of respondents (4/8) receive 4.5-6 hours of equivalent battery life across different batteries...those at the extremes of the bell curve, can you please share your specs?...

no matter what i do, i can't seem to muster any more time out of my 6-cell (4.5 hr surfing the web, 5.25 hrs working in Word)...is extreme battery life only reserved for barebone configurations?...even if i disable ethernet, modem, bluetooth, fingerprint, expresscard, card reader in the bios/device manager and turn wirless off, i can only get system consumption down to 10.5 watts...how is Kevin able to get it down to 9 W with wireless ON and screen brightness at 60%???

My specs are:

14.1 LED LCD
P8400
2 GB
250 GB
bluetooth
fingerprint
card reader
thinkpad abg wireless
XP SP3


although i appreciate how cool and silent my T400 is, the hdd fan is always spinning, maybe that's contributing to the power "drain"...i'm not disappointed by my battery life, far from it...mostly just curious how Kevin was able to achieve even greater battery life...i couldn't find it on the actual review, but someone said Kevin was running Vista...i assumed XP would be more efficient...is that an incorrect assumption?...planning to dual-boot Vista sometime this weekend to find out...anybody else want to share their battery experience? Thank you!

 

Well, from what I've gathered reading the forums the past few weeks it seems that Vista actually has better battery management than XP does. It appears that similar configurations with the difference being the OS equates to Vista having more battery life.

 

I've tested both VISTA and XP, vista isn't better.

I think the wireless card might have a lot to say, drawing a full watt or so even if not enabled, im going to test it later.
And your XP install might also be critical, some of my installs have drawn 7.8w idling, others 10w, same specs!

 

Ok, the wlan card is part of the equation:

With the Atheros produced Thinkpad bg card, disabled with the switch, the computer draws 9.8W 7/15 display idling.

With the card removed

8.25W idling.

Just having the card installed makes the comp draw 1.55W more! Christ.

 

What the heck, that's ridiculous (not you, Grkn, the card)!!...I'm in the middle of installing Vista and will compare power consumption between the two OS installations...read that Vista lets us adjust the power usage on wireless cards (Max Performance or Mainstream usage, something like that), maybe that will help battery life while surfing, but i'm surprised how much juice that component sucks while "off"...according to Power Manager, my wattage use jumps 2W when toggling the wireless switch on/off...but i didn't know it's still drawing power in the off state, too...hopefully a future driver update can improve efficiency for the Atheros card...

 

Yes, surprised me as well, but it is really the case.

I've ordered the wifi link 5300 off ebay to try that and see.

There are also differences with XP installations, the one I'm using now draws 0.625W more than another one I have :| 7.6W without the atheros card, 7/15 brightness idling is the best I've gotten.

 

I just finished installing Vista Business 32 on our T400 and all I can say is--Wow!...I installed all the necessary drivers under Vista SP1... without RMclock and without further optimizations (such as, disabling services/processes, devices, etc.) Vista is already providing 15 more minutes of battery life surfing the web, over my previous XP SP3 installation...I think the real difference is from the screen...to achieve the equivalent level of brightness as XP SP3, I could set the brightness level down 6 notches under Vista...so instead of normal surfing at 10/15 bars on XP, I only have to use 4/15 and it looks every bit as bright!!...totally unexpected...now it makes more sense to me how others are viewing their screens with only 2/15 bars, it's not as dim as it sounds!...for the record, i installed the same drivers for each respective OS and the same graphics driver for integrated graphics...with further optimizing, i'm confident i can achieve 6 hours from my 6-cell...

 

Well, a fresh install is not the same as a "old" one eighter from my experience. Basicallly Vista and XP give similar results