I ordered the memory due to the previous good opinion. I also have a Phenom II X4 on an ASUS board. Unfortunately this combination is not compatible. It always ran only one memory module and this even less than 1000 MHz. After consultation with the shipper whose previously good service I would like to emphasize the bolt be returned. Meanwhile, I have the "computer shop around the corner" two 2Gb bars of Kingston (expensive) concerned and installed. These are now running without any problems.