My current RM-72 has a voltage of 32W and S1G2 socket whereas M600-M660 with 35W and S1G3.

Does anyone have experience about such an upgrade?

Otherwise, I will upgrade from RM to ZM, which I believe not a significant step.

Have to stick with your socket version s1g2 will only work with s1g2 processors. I think ZM-84 would be a nice alternative, but you will not gain all that much on 2nd core and will get more heat. I would get an SSD drive instead to speed things up.

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