Dell XPS 9550 Tutorial of Longer Battery Life

I just purchased two 9550 recently. I believe most of the people find the battery life to be disappointing. I purchased the first Microsoft Signature Edition 9550 with i7. It runs wonderfully. No problems what so ever. Smooth and fast. I upgraded to 32GB with parts from Amazon. See no point of upgrading SSD.

My use case: majority of the time, I am typing email, browsing, and occasionally watching Youtube video. I work a lot on Powerpoint, Word and reading PDFs. That's pretty much about it. A typical office day.

However, the battery cannot last my whole day. One thing I see is that I do not use all the power that comes with the laptop. So I purchased another one from Dell, thinking i5 maybe able to save more power. Wrong! i5 consumes even more power than i7. Why? I do not know. I saw the difference in the BIOS as well. Signature BIOS has more settings while Dell one comes with a few(maybe just one) options less(both upgraded to 19 from Dell website). Since majority of the time I do not use all the power, so I started to think how to improve the battery life.

I reduced the resolution. Many people may not agree on this, If you reduce the resolution, why buy a 4K screen? My defense is that I can increase the resolution when I need it. Reducing resolution has a huge impact on the battery life.

I then change the number of active cores in BIOS from All to 2. This further reduces the power consumption. Interesting enough is the i7 can further reduce the consumption to 6,000mW or less. If I reduce the number of active cores further, the result will be opposite. So 2 is the optimal.

I then change the power profile from balanced to Low Power Profile by setting the maximum processor state to 10% when on battery, and 30% when on power adapter. I used the following Registry mod to activate Processor State setting.

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Power\PowerSettings\54533251-82be-4824-96c1-47b60b740d00\bc5038f7-23e0-4960-96da-33abaf5935ec]
"Attributes"=dword:00000002

Oh, since I do not like typing password, so I keep the screen on all the time, no sleep at all.

I tested it yesterday in a conference, it can now last a whole day without charging! The batterybar now reports my battery life to be 8:30. The other benefit is that I never heard the fan kicks in and the laptop remains to be cool to touch.

I also found the i5's battery life is not as good as i7? I have identical software installed. i7 has 32GB RAM and 512GB SSD, while i5 has 16GB RAM and 256GB SSD. Everything is like reduced in half in i5 yet it consumes more power.

If anyone is reading this thread, can you share your experience and help us increase battery life when needed.

Posted by Philaphlous in post #7 ======================================>
Use Intel XTU to lower core voltage by 100mV can further enhance battery life.

 

Have you considered an XPS 13, of you aren't doing anything heavyweight with your laptop? It's not uncommon to get 9-11 hours of battery life on a FHD (1080p) XPS 13.

Sent from my XT1575 using Tapatalk

 

I have a surface book which will easily last for 15 hours per charge. I need something with large screen and occasionally able to play games. XPS 13 is not able to play graphics intensive game(arguable?) but XPS 15 definitely is more capable. I just want a laptop that can do both and I think a lot of people has the same need.

 

Yup. If you want to play games, XPS 15 is the way to go

Sent from my XT1575 using Tapatalk

 

Also another trick is to use Intel XTU for undervolting your CPU. That should give you additional power savings... I haven't used it but I believe you can close the program without it reverting the undervolt back to default. I've heard the i7 model can undervolt -100 to -150mV...

 

I'm using -175mV right now and I think I can go lower

 

Oh my goodness, my i5 now can last for 9 hours by tuning down the core voltage to -100mV along with rest of the tricks!!

 

I have problem with XTU not applying after resuming from Sleep.
Any suggestion to make things work with Sleep?

 

Did you save it as a profile after the change? I do not have this problem...

 

Yap I saved profile
I can't pin point why after certain times, my xtu setting don't get applied.

I tried test sleep, and during testing, xtu still get applied.

Does your xtu under volt always get applied, no matter what?

 

dansi, I posted a link with a solution in the undervolting thread, when you asked about this - have you tried that?

 

I'm really surprised at all these claims of poor battery life... I'm getting about 8-9hrs on a single charge under similar use cases as the OP

 

Are you saying without any mod? Just the plain old Balanced Power Plan? That will be interesting. My batterybar will report around -20,000mW if 4 cores are used when browsing, it translates to 5 hours at most. Now with all the BIOS tuning and Low Power Plan, it reports -8,322mW but usually lasts around 8 hours only. How are you able to make it lasts 8-9 hours?

 

Yes, I've had the laptop for a little under a month, haven't fiddled with it much except to update drivers and flash the latest BIOS as they become available. I did have abysmal battery life of ~5hrs the first few days, but one of the many updates seems to have done the trick... Also, I don't turn the brightness beyond 20-30%, the white background on word docs and power ppt slides are plenty bright enough at that level for me.

 

Can you post batterybar battery prediction? If I leave my XPS unattended for 10 seconds, sometimes it will display battery life to be more than 15 hours!! It is not as accurate as battery report.

 

Was this on idling mode (no apps launched)?

 

My discharge rate is the double of his with minimum brightness

 

This is amazing. Either Sirena21 got a super XPS 15 or both of my XPS 15 have serious fault. After tuning, I am still constantly getting a 8,300mW draw when browsing. Real-life battery life is approximately 8 Hours, just enough for a whole day office work.

 

I had PowerPoint open, an e-textbook open in adobe digital editions, a couple tabs going in IE 11...

 

Something is off with our system. It should show around 10 hrs even at 8,300mW

Okay. Thanks

 

That 8,300mV was when no much activities going on. When watching YouTube or copying files or even downloading, the power draw will be going up to 13,000mW or even higher. I have been monitoring the power draw since three weeks ago when I first got my device.

 

I understand that but did the Time Remaining change when your load was 8,3000mW? If so, mind sharing what it was?

 

Mine is showing 8 hours 51 mins left when battery is at 91.2% with five tabs of Firefox, a word document and a pdf document opened. Power draw is jumping between 9,000 mW - 7,000mW.

 

With 3 edge tabs my power draw jumps between -13mW -15mW. Really don't know what to do. My CPU is undervolted to -150mV

 

I can't speak for the 9550, but with the 9350 I actually saw *increased* power draw when undervolting by a couple of W at least. This seemed counterintuitive - maybe a problem with BatteryBar's reporting, maybe something funky going on in undervolted conditions or I just wasn't doing it right. But in any case I uninstalled XTU.

 

The power draw dropped by dropping the resolution to 1080p!
EDIT: I think my battery was no calibrated. I'm at 7% for 20 minutes lol

 

What was the actual usage time you're getting before your BIOS tweak? I've downloaded the BatteryBar yesterday and for some reason the report is off. Initially it showed
4:33 @ 98.8% -8,744mW then I left it sitting on my desk running 3 hours later BatteryBar shows 3:37 @ 66.4% -9,633mW.

What's your power plan setting on battery and brightness level, by the way?

Not sure how you came up with this but the previous poster was talking about the higher current draw when undervolting the cpu which might be your case.

 

If you read the first post...

 

Read what? This " However, the battery cannot last my whole day"?

 

My original usage time is approximately 5 hours.
My current setting: Power Saver with screen always on, 10% max processor state. Turned off two cores. Brightness 10%.

 

Do not worry, you are not the only one who cannot infer anything from it...

 

I have an idea about undervolting and increased power drain...

I don't think problem is undervolting (it does not make any sense), I think the problem is Intel XTU.
If you take a look when you undervolt your processor, XTU is running in the background and in task manager you can see that it is constantly using 1-2% of the processor, which is actually a lot (30-50% of a usual idle state) and will for sure increase power drain and reduce battery life.

The solution would be to undervolt CPU and keep XTU tool off, I don't know if this is possible?


EDIT UPDATE: Actually, once you set values in Intel XTU, there is no reason to run it each time you power on your PC, the settings are applied automatically (there is an active process XTUService) when Windows starts. This XTUService does not load processor, and there is no reason to put Intel XTU to startup as many suggest!

 

Well, I would not fully agree to this. Sometimes when you come from sleep/hibernation, the settings are not automatically set, which is why I set up my own task in the windows task scheduler for it.

See here:
https://www.reddit.com/r/Surface/comments/3vslko/change_cpu_voltage_offset_with_intel_xtu_on/

 

I have not been able to get good battery life out of my XPS 15 FHD Core i7 as you can see above. First the wear was already 5% out of the box, then the computer turned on in my backpack unexpectedly and did not turn off, resulting in an additional 2% wear added. I must note though when I turned it on initially it reported 0% battery but it was not charging. This is just mainly using Chrome browsing. I did do more intensive CPU usage stuff which skewed it down but even when I changed plan to power saving and did only Chrome, I'm getting reported times of ~6 hrs only. This is with the latest BIOS and driver updates from Dell.

I am thinking about doing a drain and refill soon to "calibrate it", but I wonder if running the computer really low (like 3%) would damage it. I am also thinking about sending this computer in to at least get the battery replaced. What should I do?

update 2016/02/26 6:42AM CST - My computer has been at 7.0% for what feels like the longest time (for at least 30 minutes) when I know the 5% hibernate threshold should have kicked in long ago, so something weird is going on with the battery. I'm going to just let it sit there and drain all the way to see if that "calibrates" thing.

2nd edit - wow that seem to do it. battery bar now reports 0.2% wear. Letting it fully charge now; interested to see what the actual runtime is now on a full charge...

 

May I ask one thing? Did you boot your XPS into BIOS after Windows went to hibernate and let it die out completely to 0% in BIOS before charging it?

My battery was of 5% wear level out of the box and is now at 19% after 8 months use, which is quite frustrating.

 

Why would reducing the resolution help? The same number of pixels are still being lit, no? It may save power when gaming or whatever as there are less pixels being rendered but not by that much I would have said.

 

All the people who lower their max allowed CPU state, be warned.
There is a thing called "race to idle" which basically argues around the
question if slowing down the CPU really saves power.
If your CPU uses 10W for 8 seconds or 5W for 16 seconds doesn't matter,
but the counter argument is that the baseline consumption of the system is the
same for the whole duration anyway, so while it's true on chip level it might
not be true for the whole system. Having said that, I would not sacrifice 90%
performance for 15 minutes of battery life. I think undervolting, low brightness
and the disabling of the screen after a short time are the best ways to go.
At least for me.

 

I have the precision 5510 variant of the XPS 15. Xeon/32GB/512GB/FHD. At 50% brightness and everything in the default power settings and connected to wifi, bluetooth on, etc I get idle consumption in battery bar between 4.2 and 4.7 watts with no programs open. During normal usage (couple chrome tabs open, evernote open, working on development in eclipse, couple SSH sessions going) I average around 8W of consumption. Battery bar reports my full runtime as 10:30 - which is pretty much what I'm seeing.

I see the battery life as amazing for a Windows PC, especially one with discrete graphics and a 45W CPU.

The data I'm seeing from others in this thread is troubling. I wonder if discrete graphics aren't shutting down as they should? Or perhaps its the difference in the wifi card? (the Precision has Intel 8260, the XPS 15 has something else iirc).

--beaups