Sir Elliot’s “Volume Eleven” is a fixed Automatic-Gain-Brick-wall-Limiter with the ability of achieving very high sound pressure levels with low distortion.
Power Consumption is 2.5% using a 44.1 kHz pink noise wav file as reference. This test was conducted on a Pentium 4, 2.8 GHZ CPU using a Windows XP (Non Service Pack) operating system.
Volume Eleven may fit your requirements if you Master Rock Music.
Volume Eleven is available as a free VST plug-in for Windows.