diff --git a/artiq/gateware/targets/sayma_amc.py b/artiq/gateware/targets/sayma_amc.py
index abb614977..4fc80c5b3 100755
--- a/artiq/gateware/targets/sayma_amc.py
+++ b/artiq/gateware/targets/sayma_amc.py
@@ -251,14 +251,14 @@ class Master(MiniSoC, AMPSoC, RTMCommon):
         self.config["I2C_BUS_COUNT"] = 1
         self.config["HAS_SI5324"] = None
         self.config["SI5324_AS_SYNTHESIZER"] = None
-        self.config["SI5324_SAYMA_REF"] = None
+        self.config["RTIO_FREQUENCY"] = str(rtio_clk_freq/1e6)

         self.comb += [
             platform.request("sfp_tx_disable", i).eq(0)
             for i in range(2)
         ]
         self.submodules.drtio_transceiver = gth_ultrascale.GTH(
-            clock_pads=platform.request("dac_refclk", 0),
+            clock_pads=platform.request("si5324_clkout", 0),
             data_pads=[platform.request("sfp", i) for i in range(2)],
             sys_clk_freq=self.clk_freq,
             rtio_clk_freq=rtio_clk_freq)