I decide to test some of the CPU current measuring concepts on an old socket-7 board. Between it having single phase regulation and being disposable, I figured I couldn't lose.
First problem was the spacing of the toroids's leads. I had a devil of a time heating both at once. Eventually, I melted a big pool of solder onto the board, which conducted enough heat to the loosen the leads simultaneously.
Next difficulty was room. For my shunt I had paralleled five 0.1 Ohm resistors and there simply wasn't enough space between the socket and the nearby capacitors to place the shunt and toroid side by side.
I was forced to mount the resistors vertically, with the inductor on top and a lead returning to the board. Soldering it in was a colossal pain - the extension lead was short enough that the solder would flow at both ends. In the future, I would get some enameled wire and rewind the inductor with long leads.
Next step is amplify and digitize the reading. Last step is to add isolation, for reading from a second PC.
In the meantime, some pointless data! Using CPUburn/BurnK6 launched at high priority, a DMM, and a lot jumper changes. Current scales nicely with both Vcore and multiplier, doesn't it.
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