-// A value of 4096 should keep us within limits 32-bit systems, but I've seen
-// some minor artifacts at this level, so give it a bit more precision on
-// 64-bit systems....
-#if defined(EFIX64)
-#define FP_MULTIPLIER 32768
+// A value of 4096 should keep us within limits on 32-bit systems, but I've
+// seen some minor artifacts at this level, so give it a bit more precision
+// on 64-bit systems....
+#if defined(EFIX64) | defined(EFIAARCH64)
+#define FP_MULTIPLIER (UINTN) 65536