Keep *all* CPU cores awake?

I own a tf700t running android 4.4.4, but I'm not happy with its performance, as there are many lags.

So I thought about locking some of the cpu cores at a high frequency (yes I'm aware of the battery drain!), but I can't figure out a way to do that.

With System settings I can set the frequency, but this is only for the first core, the other cores are shut down regardless (I can check it with the app Quad Core Manager+.) With this app I tried to lock the core, but it wont work as well.

My next approach was through Tasker, but this way I can set the frequency only for cores that are actually awake!

Do you have any ideas?