@Andreas_Wolf:

>I'm afraid I don't understand your math.

It's also obvious this is how it can be computed:

if CPUA uses 1 watts for saying 1 computation "point", its computation power relatives is "1 points for 1 watts" (Perf/Power).

Now, you CPUB is 60% better on computation, for 30% of more power

Perf(CPUB) = 1.6 * Perf(CPUA)
Power(CPUB) = 1.3 * Power(CPUB)

=> Perf(CPUB) / Power(CPUB) = 1.6/1.3 * Perf(CPUA) / Power(CPUA)
=> your CPUB is 1.6/1.3 ~= 1.23 (23%) better than CPUA

And rest was a joke about "manipulating numbers to say whatever you want"... a common pratice in the marketing world ("have fun with maths"). Smile a bit...