First post here, after doing a lot of research I decided to tap the brains of the experts.
I have the 15" late 2008 unibody mbp with Penryn P8600 CPU and switchable GPU. I got it as a refurb and have owned it for little more than a year, and during the entire time I have never been able to get more than 2-3h of battery life out of it. Contrast that to the tests and users here reporting up to 5h. Here is a chronological list of things I have done to figure out what's going on:
I am using MiniBatteryLogger to monitor health, which is good, and battery current, which is alarmingly high. I also gave CooBook a shot, but only in the Freeware demo mode, where it shows me that my CPU is running at the lowest possible clock speed of 1.6GHz when idle, which seems OK.
Still, even when the machine is completely idle, bluetooth and WiFi off, brightness way down, and only a single browser (no flash) or PDF document running, I don't get more than 3h where I should be getting 5h or more. In a more typical situation with medium brightness, Wifi, email, iTunes and a couple of documents open, I am immediately down to 2h, and if I switch on the 9600m GPU and do some processor heavy stuff, I can burn through a battery in little more than 1h.
As I said I already did a lot of research and consider myself fairly knowledgeable in all things Mac, so I guess this is more of a rant than really hoping for a solution. In fact I am beginning to resign myself to the possibility that I' just have to pick up an iPad for the two or three international flights I do every year, rather than trying to squeeze an extra hour out of the mbp. Still, any information would be appreciated.
I have the 15" late 2008 unibody mbp with Penryn P8600 CPU and switchable GPU. I got it as a refurb and have owned it for little more than a year, and during the entire time I have never been able to get more than 2-3h of battery life out of it. Contrast that to the tests and users here reporting up to 5h. Here is a chronological list of things I have done to figure out what's going on:
- Upgraded to Snow Leopard 10.6, hoping it has better Battery mangagement
- Got the entire lower case replaced on Applecare, Logicboard was fried
- Bough a new battery, old on was giving "Service Battery" warnings
- Just the other day installed a fresh copy of Leopard 10.5 on a separate partition to make sure there is absolutely no software running in the background
I am using MiniBatteryLogger to monitor health, which is good, and battery current, which is alarmingly high. I also gave CooBook a shot, but only in the Freeware demo mode, where it shows me that my CPU is running at the lowest possible clock speed of 1.6GHz when idle, which seems OK.
Still, even when the machine is completely idle, bluetooth and WiFi off, brightness way down, and only a single browser (no flash) or PDF document running, I don't get more than 3h where I should be getting 5h or more. In a more typical situation with medium brightness, Wifi, email, iTunes and a couple of documents open, I am immediately down to 2h, and if I switch on the 9600m GPU and do some processor heavy stuff, I can burn through a battery in little more than 1h.
As I said I already did a lot of research and consider myself fairly knowledgeable in all things Mac, so I guess this is more of a rant than really hoping for a solution. In fact I am beginning to resign myself to the possibility that I' just have to pick up an iPad for the two or three international flights I do every year, rather than trying to squeeze an extra hour out of the mbp. Still, any information would be appreciated.
