[HTC Sensation] Arie-:
For people wondering how to set different values, I have a script (copy pasted and adjusted) in my init.d folder that sets voltages and frequencies on boot. My theory, but this is one difficult to objectively test, is that having a high speed single core setting, prevents the kernel from quickly enabling the second core which therefore should help reduce battery drain. I only use SetCPU and System Tuner to check whether my settings were applied correctly.

#!/system/bin/sh
echo "192000" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
echo "1620000" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
echo "594000" > /sys/devices/system/cpu/cpu0/cpufreq/screen_off_max_freq
echo "1188000" > /sys/devices/system/cpu/cpufreq/intellidemand/two_phase_freq
echo "1620000" > /sys/devices/system/cpu/cpufreq/intellidemand/lmf_active_max_freq
echo "594000" > /sys/devices/system/cpu/cpufreq/intellidemand/lmf_inactive_max_freq
echo "192000 800000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "310500 825000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "384000 825000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "432000 825000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "486000 850000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "540000 850000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "594000 850000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "648000 875000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "702000 875000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "756000 875000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "810000 900000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "864000 900000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "918000 900000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "972000 912500" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1026000 925000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1080000 937500" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1134000 950000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1188000 975000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1242000 1000000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1296000 1025000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1350000 1050000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1404000 1075000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1458000 1100000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1512000 1125000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1566000 1150000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1620000 1175000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1674000 1200000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1728000 1225000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1782000 1250000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels
echo "1836000 1275000" > /sys/devices/system/cpu/cpufreq/vdd_table/vdd_levels