[Guide] Improving Battery Life on Windows [+Enabling Deeper C States]

Hi Guys,

First of all, thank you so much for this thread. I can definitely see improvements on my Cyberpower Evo (basically an XMG clone from what I've heard) in terms of C0% (1-2% on idle) and PKG Power (1-2W) but after doing essentially everything in the guide and then some, I still have 2 big issues.

1 - The issue I originally was trying to solve when I found this was that sometimes when I turn on the laptop, the fan stayed on consistently, there was high CPU usage on one core (like 30% but still) and the laptop was constantly going from 40 - 50C. All of this on idle. I can't confirm if these steps have fixed that issue fully or not, but it still happened on one of my reboots where I had disabled the thunderbolt port in BIOS. I also ready somewhere in the thread that this might have some relation to waking from sleep instead of a dry boot? Has anyone found a fix for this issue as I might have to RMA the machine if I cannot consistently get rid of this high CPU bug. For reference, even before all the optimisations in this post, I get around 6-7 hours on balanced doing basic tasks when this bug doesn't happen.

2 - No matter what I do, I cannot get the CPU C-States out of C2 and C3. Right now as I type I have 95% C7% in Core, but my package states are around 20% C2 and 60% C3, "PKG" reads around 80. My C0% mostly sits between 1-2 but has random jumps to like 4 or 10 for a split second even on Idle. PKG Power is sitting around 1.5W.

Some of the things I have tried, other than the basic following of the guide (essentially all of which I've done):
- I have disabled my SD Card Reader slot in BIOS as I was getting a sleep error in powercfg energy report, the mentioned Registry Edits to fix this didnt seem to exist for the SD reader (I fixed it for another USB port).
- I've tried to disable thunderbolt, as I've noted some people mention it can be an issue here. Ditto for driver updates. Only seemed to make it worse disabling it as I mentioned earlier.
- Drivers installed via Windows update, Intel update tool, direct from sources like Realtek, and I even tried Driver Booster as a last resort.
- My CPU came from manufacturer with a -50 undervolt, I haven't modified this value but I did switch from "SpeedStep" to "Speed Shift" in the ThrottleStop interface @ 128.

Overall, I am happy with the power usage for now and can make further minor modifications in the future, but I need to get this random bug and the C states fixed first.

Does anyone have any suggestions of where to go from here? Only things I haven't really tried are a full Windows reinstall and an RMA, both of which I'd prefer to avoid if I can solve this myself.

Thanks in advance!

 

Note that sometimes disabling hardware in BIOS actually causes the CPU to not enter lower power states.

Basically most comes from either this, and appropriate drivers.

 

Yeah I've since reenabled both that and "Realtek USB 3.0 Card Reader". Does anyone know if there's a generic driver for this? With it reenabled the power report is saying "missing or misconfigured drivers". I think this could still be the issue.

On the bright side, I've managed to get mostly sub 1% C0 (as low as 0.5) with 1.3-1.4W idle. If I solve this power state issue i'll be in great shape (as long as the CPU bug doesn't come back).

 

You seemed to have tried everything. I'd be at wits end if I were you. Unfortunately this is one of the things that takes time to solve, through sheer experimentation and luck. If you love your machine, I recommend keeping it until a month before the warranty expires. If you haven't fixed the issue then, RMA and get a different laptop model.

 

Yeah a fresh windows install is looking like it might be the next thing, that or I just live with it. The CPU bug at least seems to be gone (knock on wood) and with basic tasks the battery indicator is estimating like 8.5 - 9 hours.

 

Quick update on this for those following. I did a full Windows Reset yesterday. I then installed all drivers direct from manufacturer, and a couple from Intel update manager and lastly windows update. I also did a handful of things from the guide (disabled some programs but not services yet, hipm+dipm, - 50 undervolt from manufacturer remained, switched from SpeedStep to Speed Shift).

Currently sitting with about 60% C8 residency on balanced, with about 1W PKG power and 2% C0, with plenty of room for improvements if I disable some more background. Battery indicator can go as high as 11.5 hours on idle, even more than the manufacturer "up to". Seems to have been a driver bug after all. Gonna keep an eye on it as I reinstall programs incase one of those was the culprit, but it's looking like it should be sorted now. I do also still have a powercfg energy error on some on the Card Reader but since it doesn't have the Selective Shutdown option anywhere in Registry I'll just have to let that one be!

Thanks again for all the help on this, and in putting this amazing guide together!