The previous user isn’t wrong per se, but just to clarify: if the indicator light is on, the “turbo” (default) mode is on and the device is running at full performance. Turbo off means it’s downclocked.

It’s more a misnomer to call it turbo when in fact it’s just the standard speed of the device, while the mode that is actually toggled using the turbo button is what causes it to run slower for compatibility reasons.