Asus P8P67 WS Revolution - Manual (Page 37)

2.2.5 Onboard switches
Onboard switches allow you to fine-tune performance when working on a bare
or open-case system. This is ideal for overclockers and gamers who continually
change settings to enhance system performance.
1. TPU switch
This switch allows you to enable or disable the TPU function.
2. EPU switch
Turning this switch to Enable will automatically detect the current PC loadings
and intelligently moderate the power consumption.
For ensuring the system performance, turn the switch setting to Enable when
the system is powered off.
ASUS P8P67 WS Revolution 2-11