Reduce the DDR clock below 300 MHz - Reduce the DDR clock below 300 MHz Hi I use Quartus 20.3 pro for Stratix10 FPGA, DDR3 1600. need to config clock below 300MHz at the IP. at the DDR datasheet I found that I can run it slower. I have attached the error I received, is it possible to configure the IP to support slower clock? Thanks. Moti Replies: Re: Reduce the DDR clock below 300 MHz You are welcome ! Replies: Re: Reduce the DDR clock below 300 MHz HI, Yup, as you can see from your own error screenshot, it's not supported. Thanks. Regards, dlim Replies: Re: Reduce the DDR clock below 300 MHz Are you saying you want to drive the external memory at a lower speed or run the internal logic at a lower speed? The internal logic runs, based on your current setting, at 1/4 the speed (quarter rate mode) of the external memory clock. If you're saying you want to run the external memory at a lower speed, then you can't, as the message indicates.