Why is cpu p-bus always at the maximum 12.15 V?
I have noticed through iStat Menus that the P-bus value is fixed around 12.15 V. Is that normal?
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@sa46851 is the MacBook working fine, with no issues? If so, it is probably normal; some iStat sensors are always maxed out. I have not got a 2010 15" to compare this to.
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Thanks for replying. As I mentioned below, at times when the CPU is idle, the p-bus voltage is around 11.
PPBUS_G3H is normally around this voltage when the battery is plugged in (11V-12V), it should be just under 12.6V when the battery is unplugged however. I would say it sounds like this is normal
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PPBUS_G3H is suppose to be 12.56 volts. However, if your computer is working and has a green light in the charger and no signs of trouble there is no way it can be 12.16 v. If you want to know the true voltage, take the bottom cover off and measure voltage at the backlight fuse near the LVDS connector. It will have a "P" on it.
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Thanks for replying. The problem I have is related to CPU temperature. After replacing my HDD with an SDD, the CPU temp is generally much higher than before. I suppose that is because with the faster SD drive CPU has to process more data within a shorter range of time. I have reset SMC to no avail. So I control the temperature with the iStat Menus. Now I was wondering if the reason for this issue may be related to the high P-bus voltage. Of course, I have also noticed that the voltage is above 12 only when the CPU has more demanding tasks to do. When the CPU is idle, for example, the p-bus voltage is around 11. So do I need to worry about it?
I have the exact same problem. I swapped my hard drive for a ssd in my MacBook Pro 13 inch late 2011 and now all of the sudden, idle temps around 80 and sometimes 90 degrees. I don't know why, but after 20 minutes of using the computer, it drops down to normal temps around 40 degrees. My P-bus is idle at around 11,1 volts. I thought it had to do with some background process, like kernel tasks, but I could not find anything demanding high CPU usage. I'm going to put my old drive back in and see if that makes a big difference.
