How to generate 128-bit DDR3 interface on Cyclone 10 GX

Interfaces may be supported that wide but the device you've selected may not be large enough to accommodate what you want. Things to try:

Create an example design. Configure the IP the way you want and then generate the example design on the tab in the IP Parameter Editor. See this training:

https://www.intel.com/content/www/us/en/programmable/support/training/course/omem1122.html

Use Interface Planner. After generating an example design or generating just the interface to connect to your user logic, synthesize and use Interface Planner to see what your options are for placement in the device. See this training for details:

https://www.intel.com/content/www/us/en/programmable/support/training/course/oblueintro.html

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