root@raspberrypi1:~# for i in 10 100 1000 10000 100000 200000 500000 ; do rmmod i2c_bcm2708 ; sleep 1 ; modprobe i2c_bcm2708 baudrate=$i ; sleep 1 ; echo "* $i" ; time i2cdetect -y 1 2>&1 >/dev/null | grep real ; done
* 10

real    0m0.201s
user    0m0.000s
sys     0m0.020s
* 100

real    0m0.082s
user    0m0.010s
sys     0m0.010s
* 1000

real    0m0.328s
user    0m0.010s
sys     0m0.010s
* 10000

real    0m0.168s
user    0m0.010s
sys     0m0.020s
* 100000

real    0m0.066s
user    0m0.010s
sys     0m0.020s
* 200000

real    0m0.035s
user    0m0.010s
sys     0m0.010s
* 500000

real    0m0.031s
user    0m0.010s
sys     0m0.010s
root@raspberrypi1:~#