Precision M4600 Battery Life with FirePro

i think for heavy load no one expects it to run more than 2 hours. wifi/office stuff more important to see if it lasts

 

Okay after charging my laptop last night, I played with it this morning. I have some very interesting results. Remember, I only have a 6 cell battery (about 61 Wh). All tests were done at medium brightness on the power saver config.

With the Quadro 2000M disabled:
I only get about 3 hours of battery life on a full charge.

With the Quadro 2000M enabled:
I get about 4 hours of battery life. I do have the non-IPS screen, and I have confirmed that Optimus does work so it is definitely doing its job. Optimus gives me another full hour of battery life.

EDIT: This was done while browsing the internet with 2-3 tabs open.

 

its still puzzling as its a far cry from the thinkpad W520 which has similar specs but gets 6 hours

 

Do you mean Optimus disabled? Cause if the Quadro was disabled, you should be getting longer battery life.

 

Nope. I went in to device manager and disabled the Quadro. I can go to BIOS and disable Optimus if you want me to.

EDIT: I disabled Optimus in BIOS and the battery life is slightly less than 3 hours. I'm convinced Optimus does some tweaks that us users cannot.

 

Are you guys using the Dell supplied video driver or the Nvidia Verde?

 

What I meant was, if there was some kind of Dell-specific power plan, is it possible to disable it and use the default Windows power savings settings instead?

When you disable Optimus in the BIOS, what you are actually doing is making the discreet GPU work the entire time so the battery life decreases. Your Optimus battery life actually makes sense: if you take the 4 hours you get with Optimus and multiply it by the ratio of the battery capacities (about 1.5), you get 6 hours which is in the neighborhood of what the ThinkPad W520 gets with the same configuration.

Your battery life with Optimus disabled is not that far from what havoctex claimed: 3 hours * (97Wh / 61Wh) = 4.8 hours which is not quite the 5.8 hours he was talking about, but it's not off by a factor of 2 like the FirePro lifetime. So either he was wrong about the FirePro getting a similar time as the Quadro or AMD's drivers are doing something fishy.

BTW, has anyone tried installing the regular Radeon drivers? tomcom2k in the M6600 thread did it for the sake of higher gaming performance, but maybe it will help battery life as well?

 

I think you guys should at least try the Verde(NV) and FirePro drivers straight from them first.

If you're not doing the safe mode driver sweeper install you're probably wasting your time with different drivers. All it can take is having the wrong version of one dll to pooch something.

The Optimus drivers are built into the Verde (used to be separate a year ago). I'm still not able to find a changelog or version numbers for Optimus drivers anywhere, though.

I know this thread was targeted at the FirePro, but you've got to troubleshoot both cards to see where(if) there is a problem. There are -some- helpful posts on Nvidia's Optimus section - at least for some games:

NVIDIA Forums -> Optimus & Hybrid Graphics

 

I will definitely play around with it more tomorrow. The only thing that makes no sense to me is that when I have Optimus enabled in BIOS and I disable the Quadro in device manager my battery life goes down. In theory it should go up. I don't know. I will report back anything new that I find out.

 

No, it should go down as it does. When you "disable" the Quadro in device manager, you are not actually turning the hardware off, you're just stopping Nvidia's drivers. This prevents Optimus (which actually was turning the hardware off) from doing its job so your battery life goes down. To truly disable the Quadro, you'd need some kind of option in the BIOS or OS which Dell did not implement.