Is the np8690's battery life really that abysmal?

Notebook review reported <1 hour of battery life when surfing the interwebz.
In contrast, xoticpc reports 1 hour and 30 minutes of battery life...

Both rigs have a spec of about:

• 15.6-inch 1080p (1920x1080) display with LED backlighting
• Windows 7 Ultimate 64-bit
• Intel Core i7 920XM processor (2.0GHz/3.2GHz Turbo Mode, 8MB L3 cache)
• Nvidia GeForce GTX 280M 1GB graphics card
• 8GB DDR3-1333 RAM (2x 4GB)
• 500GB 7200RPM hard drive (Seagate Momentus 7200.4/ST9500420AS)
• Intel Wireless WiFi Link 5300AGN
• 8X DVD burner
• 3-cell Li-polymer battery (3800mAh/42.18Wh)

I'm looking at this laptop at xotic pc, and i'm planning to customize to

• 15.6” FHD 16:9 LED Backlit Wide screen (1920x1080) Super Clear Glare Type Screen
• windows 7 home premium
• Core i7 820qm/ i7 620m (depending on battery life, would like a quadcore..)
• Mobility Radeon HD 5870
• 8GB DDR3-1333 (2x4GB) ram [have to tone down to 1066MHz for the 620m, might drop down to 6GB]
• 500GB 7200 RPM drive
• Intel® Ultimate-N 6300 - 802.11A/B/G/N Wireless LAN Module
• 8x dvd burner
• 3-cell Li-polymer battery (3800mAh/42.18Wh)

The specs are mostly lower than the testing rigs above, and the processor for sure generates less heat... and probably consumes way less power. The graphics card has a lower TDP [50w for the mobility radeon hd5870 and 75 for the gtx 280m] so I'm crossing my fingers for lower power usage as well.

Do you think that with my spec I could reach 1:30hrs to 2hrs of battery life with the i7 820m? How about with the 620m? because that's really all I need. If not, how much battery life could I expect, and what could i cut to raise it up? [besides downgrading to an i5-520m]

Thanks

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Edit: usage for my laptop on the run
Word processing; web browsing; coding with either eclipse, vc#, dreamweaver, notepad, and so on; image editing with fireworks and paint as a rarity.

 

i have an i7 720qm and id say id be hardpressed to get 1:30 hrs on battery.
im sure you wont get 2hrs unless its on idle.
also i believe the 5870 is closer to 75w owing to the gddr5 power draw ( anyone correct me if im wrong).
id say realistically you would max out at 1:15hrs while surfing, with everything on low and browsing on one tab.

check out this thread for some of the external battery option others have suggested:
http://forum.notebookreview.com/sager-clevo/492219-w860cu-thought-improvment-sound-battery.html

 

On mine, the battery is at 11% after watching a 46 minute movie with earphones plugged in and my screen set to the lowest level. The Dual Core might give you a bit extra but I doubt it would be much.

 

The question is whether the GPU was downclocked for the battery life tests. In most of them, I'd expect it wasn't, because the drivers don't do it by default and you have to do it manually.

 

underclocking the GPU wont give as much battery life as one more minute. underclock only cools your laptop.

this said, the battery life IS abysmal. i have done my tests, and with max saving settings you get something like 2% every minute. so 100% = 50 minutes.

and yes, the problem is not the CPU, is the GPU. we, 5870 owners, are waiting for a bios which will undervolt the vga card in order to get more battery life.

 

As someone mentioned here before, consider the battery a backup UPS.

 

You will never get decent battery life unless laptop manufacturers start using switchable solutions more. For example the M11x.

 

1.5hrs to 2 hrs?

Err...you'll be lucky to get 1hour. And that's surfing the web on power saver options, lowest brightness, GPU downclocked to 300/300, CPU in Silent Mode and all USB peripherals unplugged.

The problem is that your GPU will draw a lot of power even when downclocked. Unless we find some way to undervolt it, we won't be increasing our battery life. Even then, we'll probably be lucky to bump it up to 1.5hrs of web surfing.

 

Do you know when this bios will come?

 

Even with the GPU running at the absolute lowest clocks from a bios update you cant expect much more then a few minutes extra...

The battery is just tiny in the machine and there is not much you can do about it sadly..

 

It's possible to get 1.5 hours out of the laptop, but only under the prime operating conditions that we laptop builders love - dual core processor, SSD, and all settings as low as possible. Everyone else here has nailed it - for real world applications, your battery life is roughly an hour.