raspberry pi b+ overclocking options

SoC (Broadcom BCM2835 ARMv6) thermal range is up to +85 °C.

Orginal /boot/config.txt

disable_commandline_tags=1
gpu_mem=32
device_tree=rpi.dtb
device_tree_address=0x100
kernel=uboot.img

My additional options (stable system):

arm_freq=900
arm_freq_min=700
gpu_freq=250
gpu_freq_min=250
core_freq=450
core_freq_min=250
sdram_freq=500
sdram_freq_min=400
over_voltage=0
over_voltage_min=0
initial_turbo=15
temp_limit=75

source