Do the voltage mod or buy a voltage regulator, dropped my delta from 7000 RPM to 4200 RPM and the noise is much better,
Still when i am playing games or doing some hardcore number crunching, like so 3D cad then i just switch it back to 7000 RPM and live with the noise,
Its like having 2 coolers,
Funneling a big fan down didn't work as well for me, but..............