battery estimate

im a little worried as to the health of my battery. just last week, my 93% charge would estimate me about 2.45-3.15 hrs. now, my 92% is at 1 hr 38 minutes. im running the same two apps (mail, safari for homework) that i was running last week.

is this type of abrupt battery drop off common?

P.S. does a bigger HD require the fans to turn on more? i used to average about 1500 rpms with my 80gb, now im hovering around 2700 rpms with my 250gb. perhaps this is a reason for the battery drain?

or it could just be paranoia

is it a ac adaptor hd? also check your apps that are runing casue more apps could be runing then you think

nope, the hd is internal. there were no apps on my dock running other than those two. my activity monitor showed nothing out of the ordinary, and i "train" my battery once every month or two.

If I read your question correctly, you also changed your hard drive out? A 250 GB drive may have very different power requirements than an 80 GB drive.

size of a drive does not change how much power it uses, in fact a newer drive might even use less power, the only change would be if he had went from a 5400RPm to a 7200RPM drive, which it being a 250, he stuck with 5400, or even 4200.

have you calibrated it lately? run on battery power until it forces the machine to sleep. wait until the light on the lid release button runs out (may take a long time so you might want to do it over night). once the light is out charge all the way. you can use it during the charing. this may help, i had the same problem you had and it helped my battery life. if you haven't ran the battery update in software update you might want to do that also.

Not really related to your problem, but this little app gives you some handy battery info: http://www.coconut-flavour.com/coconutbattery/

DigitalN. said:

size of a drive does not change how much power it uses, in fact a newer drive might even use less power, the only change would be if he had went from a 5400RPm to a 7200RPM drive, which it being a 250, he stuck with 5400, or even 4200.

Click to expand...

Well, here's where some simple math & research will help:

A WD 250 GB 5400 RPM SATA notebook drive uses 2.0 WATTS of power, at idle.
A Fujitsu 80 GB 5400 RPM SATA notebook drive uses .65 WATTS of power, at idle.

And with higher wattage comes higher heat load. Of course, the under load rates are 2.5 and 1.9 W, so either way you are using more power. Thus more fan use, and more battery drain.

Source: http://www.westerndigital.com/en/products/Products.asp?DriveID=314
Source: http://www.fujitsu.com/global/services/computing/storage/hdd/mhdd/mhw2xxxbh-catalog.html