I've just bought an acer aspire 4830TG with nVidia GT540M & core i5. It also has Nvidia Optimus.
As you can see that the gpu load was initially high because i was playing game, and as soon as i close the game the gpu load went down.
However, the clock speed remains the same.
Shouldn't the gpu clock speed goes to idle when the gpu is not in use as it switches to integrated gpu??