Is It Drawing Too Much Power?

Discussion in 'MacBook Pro' started by PannaKO, Oct 10, 2015.

  1. PannaKO macrumors newbie

    Sep 12, 2014
    I've searched around and contacted AppleCare, but I couldn't find an answer from either.

    I've compared the readings of when the Macbook Pro was 2 Weeks old and now 9 Months old
    and the one that's concerning me is the DC In and CPU Package Total readings from iStat Pro.

    Before: DC In - 0.00 V CPU Package Total - 3.27 W
    Now: DC In - 20.18 V CPU Package Total - 13.04 W

    Both were in similar usage (Safari, VLC Player and EyeTV).

    I've recently received an electricity bill which is around 5x the normal amount and I'd like to rule the Macbook out.
    Is this behaviour abnormal in comparison to yours? Any help very much appreciated!
  2. joe-h2o macrumors 6502a

    Jun 24, 2012
    The Macbook Pro *at maximum* will draw 85W from your house mains (15"), or less (65W for the 13"), so if your electricity bill has jumped up by 5x then looking at the MBP as a source of problems is like trying to bail out the Titanic with a shot glass.

    The numbers given by iStat pro are normal. The "Before" is a measure of the DC-in board when the power adapter is not connected (i.e., you are running on battery power), and the "after" is when it is plugged in. This is totally normal: when you plug a power adapter into the computer it supplies power.

    The CPU package total is also normal. These numbers fluctuate a lot because the voltage of the package is low (circa 1 or 2 volts), so the current and power numbers will swing between large extremes depending on exactly what the CPU is doing on a millisecond timescale. Again, totally normal.
  3. PannaKO thread starter macrumors newbie

    Sep 12, 2014
    Thanks for the thorough explanation and helping me understand, joe-h2o.

    I did think the 'DC In 0.00 V' was odd, although I wouldn't know why it wouldn't have been plugged in when I took the readings.

    So, I assume from your assurances that your DC In readings is close to 20 V when plugged in, from Idle or just with Safari open? I'd be ruling out the Macbook for sure if that's the case for you and others.
    The CPU usage and consequently the Temps are much higher than ever before doing the same tasks (even accounting for age and dust accumulation) triggering the fans to top speed, it's been like this for about 1-2 months and hasn't been a gradual thing.

    I still have concerns that with such high/higher CPU usage almost 24/7 could still be a strong contributing factor?
  4. snaky69 macrumors 603

    Mar 14, 2008
    13W is less than even some LED lightbulbs. The MacBook Pro DEFINITELY isn't your culprit.

    Depending on whether you have a 13" or 15" (which you did not mention), it'll draw, at a maximum 65 or 85W. Even 85W isn't all that much, the light fixture in the room is likely using more.

    The big power draws in a home is heating, cooling, and the dryer. Have you been using more of those 3 lately?
  5. snaky69 macrumors 603

    Mar 14, 2008
    How long has it been since you've rebooted?

    Did you install any new software in that time frame? Fans don't come on for no reason, something is eating away CPU cycles.
  6. PannaKO thread starter macrumors newbie

    Sep 12, 2014
    I have the 2014 15" dGPU max specs. I couldn't figure the way to calculate how much power was being used in total from the readings (whether CPU package was total or only part of energy use). Using a energy calculator from a web source that may or may not be up-to-date, would support what both of you say :), even if I were using 60W 24/7 for a year.

    To my knowledge I haven't been doing anything out of the ordinary, that's why I've been looking at the Macbook suspiciously :mad:, since it's the only thing I've noticed that has been behaving more differently than before.

    I don't reboot very often. The longest I've not rebooted for, in the 9 month period I've had the Macbook, has probably been around 2 months.

    No new programs either, it's mainly Safari, VLC and EyeTV that is used at the same time (VLC playback is usually paused when EyeTV is recording if that's relevant).

    I think it's mostly EyeTV using most of the CPU, when it's recording I think it uses around 20-30% - but the temps were never a problem before, just in the last couple of months.
    EyeTV increases Kernel Task CPU usage as well, temps hover around 68-86° (rather than the usual of 47-58°) and it's when I open new tabs or surf in general with Safari, that tips it over to 91-99° and the fans come on.

    I thought that EyeTV (/VLC) were not optimised properly for the latest updates of Yosemite (and now updating to El Capitan, has not made a difference). Because, when EyeTV is behaving badly, Safari uses an unusual amount of CPU as well - like maybe there's some weird interference when used in combination and the dGPU's turned on.

    Appreciate the help snaky69, apologies if it seems like i've rambled a bit, just wanted to give you guys as much info as possible

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5 October 10, 2015