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My two month old MacBook Pro is displaying some odd behaviour when charging the battery.

According to iStat Pro, the "mem controller" fluctuates between extreme values - everything from "126 degrees Celsius" to "46 degrees C" to "-56 degrees C".

That's right - according to the stat the mem controller is actually freezing at times.

It fluctuates fast, but once I remove the power cord, and just run it on battery, everything goes back to normal, and the fans calm down.

When charging, the fans run between 4500 and 6000 RPM constantly - very annoying. Note: The machine does NOT feel hot when the fans are going full speed.

I have already tried unplugging the battery, and removing, then re-inserting, my RAM.

Hardware test fails if I run it when charging, then shows everything as perfectly fine when on battery. I just tried resetting the SMC, but it doesn't seem to have had any effect.

Any ideas? Next stop repair?

First, check Activity Monitor in the Utilities folder to make sure that this is not a software issue. Organize the processes by %CPU and see if anything is using an extraordinary amount of the CPU. If not, there may be something wrong with the temp sensor. Take it to an Apple store for a repair.

Steve

Is it actually a problem or just a display issue?