which processor is better for the battery life on z series ?

i saw that there are 3 available processors on sony z series.

1 - Intel® Core™ 2 Duo Processor P8700 (2.53GHz)
2 - Intel® Core™ 2 Duo Processor P8800 (2.66GHz)
3 - Intel® Core™ 2 Duo Processor P9700 (2.80GHz)


the 3 processors will give me enough power, but i travel a lot, and i care a lot about the batter life, so which one is better for the battery life on z series?

beside please help me with some advices in the hardware configuration to get the longest possible battery life .

thanks

Edit: thanks heavenly_wild

 

Hey there,

You may wanna edit your post and use the word "series" rather than "serious" because it took me a while to figure out what you needed. Anyway, English is a funny language.

I would suggest that you go with a P8xxx series processor if battery life is very important to you. The P9xxx series will be of course more powerful but it will use more battery.

 

Theoretically P8700 uses slightly less power on average than the other 2, just because it is slowest at full speed. P9700 has a 28W TDP, apart from the other two with 25TDP.

However I would go for P9700 because the level 2 cache is 6MB.

 

so lets say i will got the P8700 , then what about the ram ?

if i got those 3 ram options :-
1 - 4GB DDR3-SDRAM (DDR3-1066, 2GBx2)
2 - 6GB DDR3-SDRAM (DDR3-1066, 4GBx1 + 2GBx1)
3 - 8GB DDR3-SDRAM (DDR3-1066, 4GBx2)

will it make any difference on the battery life if i chose any ram from the 3 options above ?

 

RAM doesn't really affect battery life. Even if it does, it is not possible to calculate. It is the processor that's going to eat up your battery life.

You may wanna get the model with two SSD drives to save more power.

 

Or get an extra battery vs SSD (cost wise)

 

Processors underclock when they're idling. I assume that if you want the best battery life you won't be running intensive tasks while on battery so all 3 processors should clock down to the same speed and therefore will have very similar power consumption.

 

Or,
you can always customize the processor power management at advanced power option for
1. minimum processor state
2. maximum processor state

 

None. Owners of Vaios have complained of a battery drain when the laptop is turned off. Best to avoid Sonys.

 

As AlexMcIver said, all the CPUs will underclock when idle, and to the same multiple of the bus speed, so when you're not doing much, they will all run at the same low speed.

If you intermittently max out the CPU, though, like most of us do, the faster CPU will use the least amount of battery juice overall. It will use slightly more when calculating, but will finish the task faster, after which it goes into idle. Say 30 seconds at 28 W followed by 5 seconds at 4 W is better than 35 seconds at 25 W.

Only if you max out the CPU most of the time will the faster CPU be a worse choice -- then go for the P8800.

As for the RAM, it depends. Compared to the CPU, the memory usage is minimal, but the drain varies between manufacturers and chips. In general, at the same speeds, the more chips are on the cards, the more juice they will require.
For maximal battery life, using only one of the slots is optimal, but then you get less memory speed.

Another way to increase battery life is to use the much reviled Turbo Boost in Vista. Insert a fast 4 GB SD or MS card, and set it up as a turbo boost cache. It won't give you more memory, but it will be a compressed backup of most of your paging file. So when a read from the paging file would otherwise spin up the hard drive, chances are that it will just have to read it from flash instead. Not having to spin up the HD is a battery saver. (Writes to the paging file still goes to the HD, though)

The main battery saving trick is to turn off WiFi when not using it, and always run the display as dim as you can comfortably read. Secondarily, switch from Speed to Stamina mode, but unless you use 3D, you can tweak Speed mode to be pretty frugal too.