Crusial memory in Asus mobo

I believe your memory pair should work in dual channel. 'Dual channel' is a characteristic of the motherboard chipset, not the memory itself.

Crucial makes good memory, I don't see why it would not work in a dual channel setup.

The A7N8X-E mobo only has three memory slots, only two of which run in dual channel. So you are limiting your system by running two sticks of 128MB in dual channel, because your total memory is only 256MB. Your OS and other applications that run at startup are going to eat this memory. So, can they take advantage of dual channel? Not really Because when your computer requires additional memory, it is going to use your hard drive. Thus, you cannot possibly be taking advantage of a dual-channel setup.

You should use at least 512MB total memory to take advantage of dual-channel. 1GB optimal.