Thinkpads Forum

Hi guys, I've been looking around online and can't find much info on this, so I'm hoping some fellow Thinkpad enthusiasts can help me here. I just ordered two computers... a T400 with switchable ATI graphics for my wife, and a T410 with the auto switching NVidia Optimus graphics (2518-AJU) for me. The battery life on the two is drastically different, and I'm wondering if I have a bad driver, or if the T410 really does have such bad battery life.

The T400 came factory downgraded to XP. XP apparently can't support switchable graphics, so I changed it in the BIOS to integrated. Awesome battery life, like 9:30 or so on the nine cell.

We then moved it to 7Pro (64), it's battery life is not as good, but still like 7 or so. Pretty good.

My T410 has 7Pro64 on it as well, and it gets about 4 hours with the nine cell - under the same kind of usage, some light web browsing.

My immediate suspicion was that even though I wasn't doing anything that required the discreet graphics, maybe a driver was leaving them on anyway or something, because 4 hours is about what I'd expect if using the graphics. However, I found a handy little tool here:
http://files.laptopvideo2go.com/Nautis/ ... _64bit.exe

The tool shows if the Nvidia card is active or not, and it says not. So, effectively I have a T410 on integrated graphics only getting 4 hours out of a 9 cell battery - is that even possible?

The incredible thing is, she has the P8700 and I have an i5 560m, so the processors are both even clocked about the same - are i5's really so much power hungrier? They're both similar computers, spec-wise - LED backlight, same WSXGA screen, lots of memory in both, same 320GB 7200rpm drive, etc.

Were the T400's really that much better on battery life than the T410's?
OR
How much battery life does a T410 with integrated graphics get on a 9 cell? Is it about the same four hours I'm seeing here, or more?

I wanted the T410 so I could have eSata and a little faster processor/graphics - but if it means less than half of the battery life, I'll get a switchable T400 and just buy an esata Expresscard!

Thanks for any advice!

In Task Manager, there is a "Resource Monitor" button on a "Performance" tab. Click it. The Resource Monitor will start, and it will show on what frequency the CPU is running. Check that it is low enough (and is not staying close to 100% all the time).

I do have a gadget that shows such things, and generally I'm sitting at about 4-8% processor usage at 1.17Ghz, which I assume is this processor's minimum clock. So it's clearly not processor racing that's to blame. Sitting, not doing anything, with brightness around 50% and a couple of web pages and PDF's open, Power Manager is saying I'm using between 16.5 and 19W. That seems REALLY high, almost as if the Nvidia graphics are actually being powered, despite the little test tool saying it's not.

Can someone with an integrated only T410 with a 9 cell and Win7 chime in on normal battery life? It would be interesting to know if my numbers are closer to that of an integrated or discreet only T410, my suspicion is that what I'm seeing it right about the same as a T410 with discreet only graphics, and if that's the case, then this automatic switching thing isn't really doing what it's supposed to.

For a frame of reference, my wife's T400 uses between 10 and 13W browsing on integrated graphics, and then between 12 and 19W browsing on discreet. I know it's a different computer with different graphics and all, but it seems like the similarly clocked processor in my T410 should be able to get about the same power consumption as the T400's integrated graphics while just browsing, if in fact the Optimus switching is working as it should and I really am using just integrated graphics while browsing.

Anyone else have an Optimus machine, or a T410 with integrated graphics, to comment on power consumption?

Interesting, I just ran the second tool in that file I referenced above, NvOptimusTestViewer, and it's showing (even with no programs open) that the GPU is constantly oscillating between IDLE and OFF. Wonder if it just turning on a couple of times every second is enough to account for the increased power consumption.

Maybe try locking the GPU to Integrated in BIOS?

I'll try that temporarily and see what the power consumption does, but obviously that's not an acceptable solution for more than a day. This T410 is the first Thinkpad that I've ever had that I've been disappointed when I actually got my hands on it. It creaks and groans when you pick it up, the ram door on the bottom has play in it (I can tap my finger against it and only then does it sit against the thing it's touching. Just kind of seems like this model didn't get the Thinkpad essence in it.

Anyway, I'll try that and report back.

JasonPAtkins wrote:Just kind of seems like this model didn't get the Thinkpad essence in it.

Yes, they just accidentally forgot to spill that liquid from their thinkpad-essence bottle on your particular laptop; probably someone on the factory just drunk it all instead of sprinkling your laptop with it

Well interesting... BIOS set to integrated only gets me an average browsing power consumption of 10.5-14w - clearly better than the Optimus. This battery life thing might be enough to make me find a new home for this laptop and get myself a second T400. Any guesses on whether this could be solved by a driver, or if it's inherent in the architecture?