code: func computeMHz(brandString string) int {
  	hz := strings.LastIndex(brandString, "Hz")
  	// ' 1MHz'
  	if hz < 3 {
  		return -1
  	}
  	multiplier := cpuFrequencyMultipliers[brandString[hz-1]]
  	if multiplier == 0 {
  		return -1
  	}
  	freq := 0
  	divisor := 0
  	decimalShift := 1
  	var i int
  	for i = hz - 2; i >= 0 && brandString[i] != ' '; i-- {
  		if brandString[i] >= '0' && brandString[i] <= '9' {
  			freq += int(brandString[i]-'0') * decimalShift
  			decimalShift *= 10
  		} else if brandString[i] == '.' {
  			if divisor != 0 {
  				return -1
  			}
  			divisor = decimalShift
  		} else {
  			return -1
  		}
  	}
  	// we didn't find a space
  	if i < 0 {
  		return -1
  	}
  	if divisor != 0 {
  		return (freq * multiplier) / divisor
  	}
  	return freq * multiplier
  }
docs: // computeHz determines the official rated speed of a CPU from its brand
  // string. This insanity is *actually the official documented way to do
  // this according to Intel*. There is also a cpuid leaf for the frequency,
  // but I am not sure how supported it is, so.