Samsung Series 7 Win 8.1 battery life problem

Hello all,

I recently was forced to upgrade from Win 8 to Win 8.1 on my Samsung NP700Z5C. Since this change, I have roughly half the battery life left. However, I haven't changed anything since the upgrade. Is there any possibility to restore the original battery capacity? It is very strange, since I don't have any increased CPU usage or anything and yet am left with about 4hrs of battery compared to 8+ before the update.

Thanks,
Sepp

 

Get BatteryInfoView and see what it reports with the computer running on battery.

How does the current capacity compare to the Design Capacity and the Full Charge Capacity?

What is the discharge rate?

To get 8 hours run time you need a discharge rate that is averaging about 10W (10,000mW).

Did you reinstall Samsung's Settings program after doing the Windows upgrade? If not, it is possible that Windows has lost the Samsung power tweaks and the reinstallation of Settings (which includes a lot of background configuration) will get things working better.

The other possible culprit is the graphics and maybe the discrete GPU is running when it should not be. Reinstallation of the graphics driver(s) might sort this out.

John

 

Hi John,

Thank you very much for your hint. These are the stats BatteryInfoView is showing me:

Description Value
Battery Name
Manufacture Name SAMSUNG Electronics
Serial Number
Manufacture Date
Power State Discharging
Current Capacity (in %) 79.0%
Current Capacity Value 56'122 mWh
Full Charged Capacity 71'040 mWh
Designed Capacity 80'216 mWh
Battery Wear Level 88.6%
Voltage 16'011 millivolts
Charge/Discharge Rate -12'994 milliwatts
Chemistry Lithium Ion
Low Battery Capacity (1) 2'131 mWh
Low Battery Capacity (2)
Critical Bias
Number of charge/discharge cycles 111
Battery Temperature
Remaining battery time for the current activity (Estimated)
Full battery time for the current activity (Estimated)
Remaining time for charging the battery (Estimated)
Total time for charging the battery (Estimated)

So although the discharge rate is fairly close to 10W, the max battery is the problem. However, it is important to note, that the very day before I upgraded to Win8.1, the battery life was at about 8 hours (used it all day), whereas immediately after the update, the battery life dropped to something around 3-4 hours... Is there any issue known, which is related to the Win 8.1 update? I have updated the "Settings" utility as well as any graphics driver after I upgraded to Win 8.1, so this didn't help. Is there any other solution known for this issue?

Sepp

 

Thank you for the extra info.

There's a long thread about problems relating to Windows 8.1.

13W discharge rate is high. Somehow you need to check which GPU is being used. GPU-z or HWiNFO might tell you this. If it is the Intel GPU then we need to dig further. What is the CPU utilization when on idle? Is the computer using the Samsung Optimized power plan?

John

 

John,

Thank you very much for your help. I checked with GPU-Z and the primary GPU is the Intel GPU. According to GPU-Z, its usage is about 5% on idle / office use. Same for the CPU, if I don't run any programs, the CPU usage barely exceeds 3%. That's why I am so confused. Compared to before the update, literally nothing changed besides the OS and now my laptop has half the battery life...
As a battery plan, I use the Windows Battery Safe Mode, which I customised (lowest brightness, etc.). Here as well, I have changed nothing on the battery savings settings, compared to before the update.

Any other ideas, what could cause this drop in battery life?

Best,
Sepp

 

You can run HWiNFO and check what the CPU speed. when on idle it should be spending almost all the time on minimum speed. If it has got stuck on a higher speed it will be using more power and probably not going to sleep. You can check whether it is going to sleep using Performance Monitor (Start>Run>Perf) and then right click > Add Counters > Processor > %C3 Time.

You can also check the effect on power drain of turning the wireless (WiFi and BT) off although those devices should not be using several watts even under the worst conditions.

John

 

John,

HWiNFO shows me a CPU clock (is that the speed?) of anything between 1197.2MHz and 1197.4MHz for each core (I have a quad core CPU). These are also the Minimum and Maximum value displayed next to it. More interstingly, Performance Monitor shows an average %C3 Time of somewhere around 95 (percent?). From your explanation, I assume, that the CPU therefore is always running on maximum speed, even in idle. Is there any possibility to change that?

Best,
Sepp

EDIT: However, the task manager only shows a speed of 1.15GHz out of 2.4GHz maximum speed. Not sure if this helps though.

EDIT: Internet Research suggested, that it could be because my BIOS is maybe updated. If this could be the cause: How do I check if I have the most recent version and would you suggest going for this approach?

 

I think that generation of CPUs has a minimum speed of 1200 MHz and the %C3 looks very good.

See the first post in this thread for a link to the Samsung BIOS update program. If there is a newer BIOS then download it first before running it.

John

 

Okay, in that case it was a wrong interpretation from my side, my bad.

Thank you for the link. I checked and the most recent update has the same name as the BIOS which is already on my laptop (P07ABJ). Any other ideas what could be the problem?

 

I'm short of other suggestions but it may be worthwhile trying this to try to discover if something is loading the CPU more than necessary. As it's a quad core then we should be aiming for half of the CPU utilisation of a dual core so 1% might be a good target.

Restart the computer and leave on idle then run Task Manager then View > Select Columns then select the CPU time column. Also select "Show Processes for all users". Then click on the header of the CPU time column to soft the processes by CPU time. I find this information to be more helpful than the %CPU which keeps changing and after a few minutes it becomes clearer which processes are using the CPU. If you discover that one of the svchost.exe is using a lot of CPU then you will probably need to get Sysinternals Process Explorer to try to track down what program is using that instance of the service.

You can also use msconfig (wherever it is hidden in 8.1) to check throught the programs that are loading on startup and see the effect of stopping some of them if their need isn't obvious.

John

 

I've been following this thread, albeit only superficially.

I saw increased background activity after updating to Win8.1, which reduced my battery time as well. Not as extreme as this, but enough that I switched back to Win8 on my Sammy. I installed Win8.1 on a desktop replacement laptop, because it is always plugged in.

In addition to what John has already suggested, one thing came to mind: Is it possible that before the Win8.1 update, you had Silent Mode enabled, which gave you much improved battery runtime? Many users enable it unintentionally, either by hitting Fn-F11 or by selecting Silent Mode=AUTO in Settings (it should be OFF for normal performance).

Please don't take offense for the banality of that suggestion. But it WOULD be a logical explanation for such a dramatic drop

 

Dannemand,

Thank you so much for your help. Although it is embarrassing to admit, but apparently the Silent Mode was on AUTO, so I switched it to OFF and the battery life jumped to 5 hours @ 80% charge. Although this is still not the life I'm used to, it made things much better.

John, Thank you as well for your contributions, I highly appreciate that you didn't lose faith! I will look if the fan mode was the entire solution, otherwise I'll reactivate this thread

Cheers
Sepp

 

Silent Mode is not something I would have thought of. It usually locks the computer down to minimum speed and is the cause of "my computer is running slowly" problems. I'm not sure how silent Mode can increase power consumption unless it slows down the hardware to the extent that it runs inefficently and reduces the amount of time the system can spend sleeping. I reckon that the most power efficient operation is to let the CPU speed up to its maximum non-turbo speed to get work done. (Turbo mode is less power efficient because the voltage is increased to ensure stability and work done per watt reduces.)

You may also discover that the system power consumption drops a bit once Windows 8.1 has finished getting itself settled in.

John

 

John is right: Silent Mode does indeed cause slower processing and thus (usually) improved battery runtime due to lower power consumption.

What I meant was if Silent Mode had been enabled (AUTO) before the Win8.1 update, thus saving power and causing the battery to last longer. Then after the Win8.1 update, if Silent Mode was no longer enabled due to Samsung Settings being updated, it would cause the shorter battery time that Master_Sepp is seeing.

As it turns out, Silent Mode was actually enabled now after the update. Maybe it was enabled before as well. But in any case does it not explain a halving of the battery runtime.

That said, it is hard to measure anything accurately with Silent Mode enabled, since the CPU is capped at a very low speed (regardless of which Windows Power Plan is selected). I can imagine some situations when a capped CPU speed might actually reduce battery runtime because a lot of CPU work is being done -- such as during and after a Windows update, when the Module Installer is running like crazy to do... whatever it does in the background. Most CPUs are more power efficient at the higher end of their speed range: If there is work to be done, it is better to get it over with fast, then get back to idle.

I would also say to make sure you stay on the Samsung Optimized power plan, which knows about Samsung's power management philosophy. I think John already mentioned that. Tweaking that power plan to your liking is generally better than switching to Windows' standard power plans (Balanced or High performance). The post here has more about samsung power management.

Beyond that I don't really have any input that has not already been suggested