two different memory for dual channel??help

hi i have this memory QDI DDR 512Mb 400Mhz (infineon/micron)(512/400)
and i thinking to buy this kingston DDR 512Mb 400Mhz NON-ECC KVR400X64C3A/512
but i want to use this two memory for dual channel.
can i use this two memory for dual cahnnel??
do i have to buy the same stick of qdi memory for dual channel?'
which of them is better?both have life time warranty.
my motherboard is asus a7v880.
please help me !!!

 

the best way is to buy dual channel is in pairs then it is pretty much garanteed to work ... mismatching sticks most likely will not work