Arch Linux

silenceleaf

Member

Registered: 2013-03-16

Posts: 38

Intel i7-4800MQ CPU Power Consuming is much higher than Windows

On Windows 8.1, I run CPU-Z to generate these information:
--------------------------------------------------------------------------------------
Processor 1    ID = 0
     Number of cores    4 (max 8)
     Number of threads    8 (max 16)
     Name    Intel Core i7 4800MQ
     Codename    Haswell
     Specification    Intel(R) Core(TM) i7-4800MQ CPU @ 2.70GHz
     Package (platform ID)    Socket 947 rPGA (0x4)
     Core Stepping    C0
     Technology    22 nm
     TDP Limit    47 Watts
     ***Core Speed    799.0 MHz***
     Multiplier x Bus Speed    8.0 x 99.9 MHz
     Stock frequency    2700 MHz
     Instructions sets    MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, EM64T, VT-x, AES, AVX, AVX2, FMA3     
     Turbo Mode    supported, enabled
     Max non-turbo ratio    27x
     Max turbo ratio    37x
     Max efficiency ratio    8x

--------------------------------------------------------------

You see: This CPU can run at 800MHz(Core Voltage 0.6 v) on windows, when there is no CPU toast Task. The fan is quiet.

===========================================================

But on Arch Linux, I run the latest i7z-git, I got these information:

Cpu speed from cpuinfo 2693.00Mhz
cpuinfo might be wrong if cpufreq is enabled. To guess correctly try estimating via tsc
Linux's inbuilt cpu_khz code emulated now
True Frequency (without accounting Turbo) 2693 MHz
  CPU Multiplier 27x || Bus clock frequency (BCLK) 99.74 MHz

Socket [0] - [physical cores=4, logical cores=8, max online cores ever=4]
  TURBO ENABLED on 4 Cores, Hyper Threading ON
  Max Frequency without considering Turbo 2792.74 MHz (99.74 x [28])
  Max TURBO Multiplier (if Enabled) with 1/2/3/4 Cores is  37x/36x/35x/35x
  Real Current Frequency 2653.53 MHz [99.74 x 26.60] (Max of below)
        Core [core-id]  :Actual Freq (Mult.)      C0%   Halt(C1)%  C3 %   C6 %   C7 %  Temp      VCo
        Core 1 [0]:       2625.75 (26.33x)      2.45    16.6       1    2.39    77.6    40      0.89
        Core 2 [1]:       2653.53 (26.60x)         1    1.14    2.44       1    94.4    40      0.89
        Core 3 [2]:       2628.92 (26.36x)      1.41     4.7       1       0    92.9    42      0.89
        Core 4 [3]:       2631.18 (26.38x)      2.29    20.4    1.44       1    74.9    39      0.89

CPU can only run at 2.7Ghz (or higher in turbo model), and Core Voltage is 0.89 v. Tha fan is very noisy.

I try many method in CPU power saving, but can not find the solution. Is there any diffierent in power management between Linux and windows?

Head_on_a_Stick

Member

From: London

Registered: 2014-02-20

Posts: 7,732

Website

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

Have you tried the "tlp" package yet? It seems to help with my power consumption with an i5-4330M...
Also, have a look at the wiki page on "CPU Frequency Scaling"

Last edited by Head_on_a_Stick (2014-02-23 21:15:37)

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silenceleaf

Member

Registered: 2013-03-16

Posts: 38

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

Have you tried the "tlp" package yet? It seems to help with my power consumption with an i5-4330M...
Also, have a look at the wiki page on "CPU Frequency Scaling"

Thank you! CPU Frequency Scaling page seems too old which not mention more about haswell CPU and pstate driver.

I am learing tlp package, wish it can slove my problem too!

silenceleaf

Member

Registered: 2013-03-16

Posts: 38

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

I tried tlp, laptop-model-tools, termald, pm-utils, cpu-frenq. I am confusing with these tools, which one is official power management tool?

Gusar

Member

Registered: 2009-08-25

Posts: 3,605

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

The CPU is only running at the shown frequency in the C0 state. Meaning, almost never, about 2% of the time according to your i7z output. In the C3/C6/C7 states, the frequency is *zero*. That's how modern processors work. You're in C7 most of the time, which is how things should be. How exactly did you measure this much higher power consumption?

You could try disabling pstate so that acpi_cpufreq will be used, and see how things are with that. But there shouldn't be a big difference.

Edit: laptop-mode-tools and pm-utils are basically outdated. thermald is a good tool to use, it was designed specifically to be used with pstate. However, in normal conditions it shouldn't be needed. Try it anyway.

Last edited by Gusar (2014-02-23 21:40:35)

Head_on_a_Stick

Member

From: London

Registered: 2014-02-20

Posts: 7,732

Website

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

I tried tlp, laptop-model-tools, termald, pm-utils, cpu-frenq. I am confusing with these tools, which one is official power management tool?

tlp is the latest-and-greatest and is probably the one you want since you have a recent processor...
NOTE: only use ONE power management solution at a time as they will conflict; such as : multiple suspend requests being sent, etc.
Also, the frequency scaling wiki page gives information as to how to set the cpu minimum & maximum frequencies ("Setting maximum & minimum frequencies" section)

Last edited by Head_on_a_Stick (2014-02-23 21:47:27)

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Gusar

Member

Registered: 2009-08-25

Posts: 3,605

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

Also, the frequency scaling wiki page gives information as to how to set the cpu minimum & maximum frequencies ("Setting maximum & minimum frequencies" section)

That section refers to acpi_cpufreq, *not* to intel_pstate. pstate has internal governors and overall works very differently from acpi_cpufreq.

Edit: Hmm, actually, those commands work with pstate too. Interesting, I recall this not being the case at the beginning when pstate was introduced. But the point remains that pstate works very differently and in general you shouldn't mess with min/max freqs because it will not have the effect you think it will.

Last edited by Gusar (2014-02-23 22:00:38)

silenceleaf

Member

Registered: 2013-03-16

Posts: 38

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

The CPU is only running at the shown frequency in the C0 state. Meaning, almost never, about 2% of the time according to your i7z output. In the C3/C6/C7 states, the frequency is *zero*. That's how modern processors work. You're in C7 most of the time, which is how things should be. How exactly did you measure this much higher power consumption?

You could try disabling pstate so that acpi_cpufreq will be used, and see how things are with that. But there shouldn't be a big difference.

Edit: laptop-mode-tools and pm-utils are basically outdated. thermald is a good tool to use, it was designed specifically to be used with pstate. However, in normal conditions it shouldn't be needed. Try it anyway.

I have read many post in arch forum, and used to believe that haswell no not need any setting in power management. But definitely, when I using windows, the difference performance of fan and temperature make me can not ignore this.

I compare the power consuming with windows. In windows 8.1 the fan do not need to work most of time. But in Linux it will run soon after laptop boot.

The core voltage explain this:
in windows: it is 0.6v (800MHz) from cpu-z
in linux: it is 0.9v(2700MHz) from i7z-git

Gusar

Member

Registered: 2009-08-25

Posts: 3,605

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

I compare the power consuming with windows.

How exactly? That was my question. Just the voltage report? Or do you actually notice something is not right, like shorter battery life? Different tools could possibly measure things differently. Try turbostat, it's in AUR.

Fan management can also be unrelated to actual power consumption. I've wondered before whether pstate, because it works differently, is confusing whatever is responsible for controlling the fans. What brand of laptop do you have? Post the output of lsmod.

And again, just because a tool says the frequency is at 2700MHz, does not mean the processor is actually at that frequency! It is not most of the time.

silenceleaf

Member

Registered: 2013-03-16

Posts: 38

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

I compare the power consuming with windows.

How exactly? That was my question. Just the voltage report? Or do you actually notice something is not right, like shorter battery life? Different tools could possibly measure things differently. Try turbostat, it's in AUR.

Fan management can also be unrelated to actual power consumption. I've wondered before whether pstate, because it works differently, is confusing whatever is responsible for controlling the fans. What brand of laptop do you have? Post the output of lsmod.

And again, just because a tool says the frequency is at 2700MHz, does not mean the processor is actually at that frequency! It is not most of the time.

Thank you for your help.

I am using dell M4800 laptop which have a 97Wh battery.  Mainly browing web page and typing some documents. In windows, its battery can last for 5 hours.  In linux, it can only last 3 hours.

I am also trying to find more evidence to compare the power consuming between these two platforms. I understand your meaning. It is hard to fairly compare these two environment. I am strill trying to find more information.

lsmod output

Module                  Size  Used by
rfcomm                 50698  12 
btusb                  19648  0 
hid_generic             1153  0 
snd_usb_audio         117811  2 
uvcvideo               72804  0 
videobuf2_vmalloc       3304  1 uvcvideo
snd_usbmidi_lib        19755  1 snd_usb_audio
videobuf2_memops        2335  1 videobuf2_vmalloc
snd_rawmidi            18742  1 snd_usbmidi_lib
videobuf2_core         28243  1 uvcvideo
snd_seq_device          5180  1 snd_rawmidi
videodev              111840  2 uvcvideo,videobuf2_core
media                  11719  2 uvcvideo,videodev
usbhid                 40545  0 
hid                    90902  2 hid_generic,usbhid
ctr                     3831  2 
ccm                     7894  2 
nvidia              10621191  2 
snd_hda_codec_hdmi     36379  1 
joydev                  9631  0 
mousedev               10247  0 
dell_wmi                1485  0 
sparse_keymap           3146  1 dell_wmi
bnep                   13053  2 
bluetooth             326343  30 bnep,btusb,rfcomm
arc4                    2000  2 
x86_pkg_temp_thermal     6991  0 
intel_powerclamp        8802  0 
coretemp                6358  0 
kvm_intel             131532  0 
kvm                   396221  1 kvm_intel
crct10dif_pclmul        4682  0 
crct10dif_common        1372  1 crct10dif_pclmul
crc32_pclmul            2923  0 
crc32c_intel           14185  0 
ghash_clmulni_intel     4405  0 
aesni_intel            45548  4 
aes_x86_64              7399  1 aesni_intel
lrw                     3565  1 aesni_intel
gf128mul                5858  1 lrw
glue_helper             4417  1 aesni_intel
ablk_helper             2004  1 aesni_intel
cryptd                  8409  3 ghash_clmulni_intel,aesni_intel,ablk_helper
snd_hda_codec_realtek    45083  1 
iTCO_wdt                5407  0 
iTCO_vendor_support     1929  1 iTCO_wdt
ppdev                   7118  0 
fuse                   76830  3 
dell_laptop            12389  0 
dcdbas                  6463  1 dell_laptop
iwlmvm                136091  0 
mac80211              474777  1 iwlmvm
microcode              15216  0 
iwlwifi               140001  1 iwlmvm
i2c_i801               11269  0 
psmouse                88171  0 
pcspkr                  2027  0 
evdev                  11045  22 
serio_raw               5009  0 
i915                  725519  5 
snd_hda_intel          37352  4 
cfg80211              408167  3 iwlwifi,mac80211,iwlmvm
snd_hda_codec         150017  3 snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_intel
snd_hwdep               6332  2 snd_usb_audio,snd_hda_codec
snd_pcm                77822  4 snd_usb_audio,snd_hda_codec_hdmi,snd_hda_codec,snd_hda_intel
intel_agp              10872  1 i915
intel_gtt              12664  2 i915,intel_agp
snd_page_alloc          7298  2 snd_pcm,snd_hda_intel
drm_kms_helper         35710  1 i915
snd_timer              18718  1 snd_pcm
rfkill                 15651  5 cfg80211,bluetooth,dell_laptop
drm                   239102  5 i915,drm_kms_helper,nvidia
lpc_ich                13368  0 
i2c_algo_bit            5391  1 i915
i2c_core               24760  7 drm,i915,i2c_i801,drm_kms_helper,i2c_algo_bit,nvidia,videodev
mei_me                  9552  0 
snd                    59029  23 snd_hda_codec_realtek,snd_usb_audio,snd_hwdep,snd_timer,snd_hda_codec_hdmi,snd_pcm,snd_rawmidi,snd_usbmidi_lib,snd_hda_codec,snd_hda_intel,snd_seq_device
mei                    62803  1 mei_me
soundcore               5418  1 snd
e1000e                222900  0 
ptp                     8244  1 e1000e
pps_core                8833  1 ptp
shpchp                 25425  0 
thermal                 8556  0 
wmi                     8251  1 dell_wmi
parport_pc             19479  0 
parport                30517  2 ppdev,parport_pc
video                  11425  1 i915
ac                      3334  0 
battery                 7565  0 
processor              24620  0 
button                  4605  1 i915
vboxdrv               264122  0 
msr                     2565  0 
ext4                  473259  2 
crc16                   1359  2 ext4,bluetooth
mbcache                 6074  1 ext4
jbd2                   80912  1 ext4
sr_mod                 14930  0 
sd_mod                 31361  5 
cdrom                  34880  1 sr_mod
atkbd                  16806  0 
libps2                  4187  2 atkbd,psmouse
ahci                   23048  3 
libahci                21698  1 ahci
libata                172104  2 ahci,libahci
sdhci_pci              12604  0 
ehci_pci                3928  0 
sdhci                  28820  1 sdhci_pci
xhci_hcd              144681  0 
ehci_hcd               64171  1 ehci_pci
scsi_mod              132250  3 libata,sd_mod,sr_mod
mmc_core               95465  2 sdhci,sdhci_pci
usbcore               180320  8 btusb,snd_usb_audio,uvcvideo,snd_usbmidi_lib,ehci_hcd,ehci_pci,usbhid,xhci_hcd
usb_common              1648  1 usbcore
i8042                  13366  2 libps2,dell_laptop
serio                  10721  6 serio_raw,atkbd,i8042,psmouse

Gusar

Member

Registered: 2009-08-25

Posts: 3,605

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

I see you have both i915 and nvidia modules loaded. Googling around, this machine does not have Optimus and the Intel GPU should be off if the Nvidia card is in use. Maybe that's what's causing lower battery life, both GPUs are active in Linux whereas Windows disables the Intel GPU.

silenceleaf

Member

Registered: 2013-03-16

Posts: 38

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

I see you have both i915 and nvidia modules loaded. Googling around, this machine does not have Optimus and the Intel GPU should be off if the Nvidia card is in use. Maybe that's what's causing lower battery life, both GPUs are active in Linux whereas Windows disables the Intel GPU.

Thank you for your help! I have bamblebee, but maybe it have something wrong, let me check, Thanks!

silenceleaf

Member

Registered: 2013-03-16

Posts: 38

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

I see you have both i915 and nvidia modules loaded. Googling around, this machine does not have Optimus and the Intel GPU should be off if the Nvidia card is in use. Maybe that's what's causing lower battery life, both GPUs are active in Linux whereas Windows disables the Intel GPU.

Hi, sorry to bother you again.

My Dell M4800 have two fans, left is for CPU, right for GPU. Although my bumblebee may be something wrong that Nvidia GPU and intel CPU modules are all loaded, the heat from the CPU side is very high than in windows and fan working all the time. So, I guess the power management for Intel CPU is not efficient.

I can not exactly describe why I fell CPU's power consuming is unusual. In windows light task, the CPU fan do not work all the time, but in Linux light task, the fan have to work after half hour and can't stop.

Can you give me some hint to check the reason of this problem? Thank you in advance!

silenceleaf

Member

Registered: 2013-03-16

Posts: 38

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

I see you have both i915 and nvidia modules loaded. Googling around, this machine does not have Optimus and the Intel GPU should be off if the Nvidia card is in use. Maybe that's what's causing lower battery life, both GPUs are active in Linux whereas Windows disables the Intel GPU.

Thank you for your help! I have bamblebee, but maybe it have something wrong, let me check, Thanks!

Oh, BTW, in windows, I install intel and nvidia driver both, and only use Intel Graphic card in most cases.

Gusar

Member

Registered: 2009-08-25

Posts: 3,605

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

Do you have the QHD+ (3200x1800), or the FHD (1920x1080) display? The QHD+ variant doesn't have Optimus, the FHD does (I think, I'm not completely sure).

So if you're using bumblebee, is it actually working? As in, is the Nvidia card off most of the time?

Last edited by Gusar (2014-02-24 21:56:06)

silenceleaf

Member

Registered: 2013-03-16

Posts: 38

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

Do you have the QHD+ (3200x1800), or the FHD (1920x1080) display? The QHD+ variant doesn't have Optimus, the FHD does (I think, I'm not completely sure).

So if you're using bumblebee, is it actually working? As in, is the Nvidia card off most of the time?

I have FHD display. You mean if I want to power off nvidia card, I should not see the module name in lsmod after machine startup? I do some configuration of bumblebee, but I still can see the nvidia module display in lsmod. May be something wrong in configuration, I check it myself.

As I said above, I fell the reason is not on my nvidia card. The CPU side is hot and fan working all the time, the GPU side fan is cool. These two fan have two heat pipe and they are independent.

Gusar

Member

Registered: 2009-08-25

Posts: 3,605

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

You mean if I want to power off nvidia card, I should not see the module name in lsmod after machine startup?

I don't actually know, I have never used an Optimus machine.

As I said above, I fell the reason is not on my nvidia card. The CPU side is hot and fan working all the time, the GPU side fan is cool. These two fan have two heat pipe and they are independent.

You said nothing about temperature before. Your i7z output is showing 40 degrees, for a mobile i7 processor that looks normal to me. Is it lower in Windows?

Anyway, have you tried disabling intel_pstate? I don't know right now how to do it, but I'm sure it's written in some wiki page somewhere.

Arup

Member

From: Earth

Registered: 2014-02-20

Posts: 95

Re: Intel i7-4800MQ CPU Power Consuming is much higher than Windows

It seems that your nouveau is on, make sure to remove TLP if you have it installed for now, it turns the nouveau on. My battery consumption on IVB i7 Optimus is same as in Windows here.

Last edited by Arup (2014-02-27 11:21:37)