Underclock GPU to save battery life?

Soldato
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5 Jul 2007
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I have a GT330m 512MB in my laptop. Works well for the games I play but in Windows this means I get quite poor battery life. I have read of people overclocking these using Nvidia performance tools, but what about the opposite?

Are there any problems with underclocking it to save even more juice when just watching a film or doing work on a train? Would this help with battery life?
 
I've configured the "Power saver" mode to low power settings that I would use so now I can select that at a click of a button.

I've reduced the graphics card to the lowest it will go in the nvidia control panel after installing the performance tools and the battery meter on the laptop added over an hour more of estimated time so the proof will be in testing now. Power saver mode added about 30 mins or so to the estimated battery time then another hour appeared when I underclocked the graphics card.

CPU is locked by the looks of it but I would have hoped that new intel CPUs underclock themselves automatically when not in use as the old ones used to! Computer properties show it still at full speed though so maybe Windows 7 reports the maximum speed all the time so it's not possible to see the current speed like in the XP days?
 
You can use GPU-Z and CPU-Z tools to see what the clocks of both are running at.

Quality cheers. Nvidia Tuner works off profiles so I've made two icons. One called "Standard" and one called "Underclock" so when I'm on the train I click underclock on the desktop and it underclocks the card. If I want to play a game or something at some point then I just plug the AC power in and go back to standard settings again. Simples!

GPU-Z confirms the clock speeds so I'm happy now :D Although I cannot go back to standard whilst on battery for some reason! It will let me go down clock speed but not go up whilst on battery lol. Even if it is going back to factory defaults! Says invalid values... :confused: Read online that it is to do with being on battery and as soon as I plugged in the AC power I could go up again the standard power. Strange.
 
TBH even with a massive underclock I doubt clocking the GPU down in 2D mode is going to make much difference to battery life - maybe a couple of minutes.
 
have you also got dimmer control for the screen, that usually saves a bit.

or better still plug it in and don't run from the battery :)
 
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