Problem DDR2 bandwidth

Hi,

I'm working on the cyclone IV GX dev board and using DDR2 SDRAM for stocking images coming from a camera.

In the documentation of the dev board, the maximum theoretical bandwidth of the DDR2 is 10.6Gbps. But in my case, i have just 200Mbps when i read from DDR2. this is a problem because i have under 10ms to process two images (752x480).

Of course, I use burst.

I'm using the "DDR2 SDRAM-controller with ALTMEMPHY" to control the DDR2.

I have posted my SDRAM-controller configuration to help you.

Does anyone know why the bandwidth is very bad?

Thanks

hallodu