diff --git a/sys/i386/conf/XBOX b/sys/i386/conf/XBOX
index 0c942ffd0ea..4c749b2da0a 100644
--- a/sys/i386/conf/XBOX
+++ b/sys/i386/conf/XBOX
@@ -42,6 +42,8 @@ options 	CD9660			# ISO 9660 Filesystem
 #options 	_KPOSIX_PRIORITY_SCHEDULING # POSIX P1003_1B real-time extensions
 #options 	KBD_INSTALL_CDEV	# install a CDEV entry in /dev
 options 	ADAPTIVE_GIANT		# Giant mutex is adaptive.
+# Xbox has a non-standard default timer frequency
+options 	TIMER_FREQ=1125000	# Gives ~733.34MHz CPU
 
 #device		apic			# I/O APIC
 
diff --git a/sys/i386/isa/clock.c b/sys/i386/isa/clock.c
index f785849faca..652cc0144cd 100644
--- a/sys/i386/isa/clock.c
+++ b/sys/i386/isa/clock.c
@@ -93,10 +93,6 @@ __FBSDID("$FreeBSD$");
 #include <i386/bios/mca_machdep.h>
 #endif
 
-#ifdef XBOX
-#include <machine/xbox.h>
-#endif
-
 /*
  * 32-bit time_t's can't reach leap years before 1904 or after 2036, so we
  * can use a simple formula for leap years.
@@ -543,11 +539,6 @@ calibrate_clocks(void)
 	return (tot_count);
 
 fail:
-#ifdef XBOX
-	if (arch_i386_is_xbox)
-		timer_freq = 1125000; /* gives ~733.34MHz CPU clock */
-#endif
-
 	if (bootverbose)
 	        printf("failed, using default i8254 clock of %u Hz\n",
 		       timer_freq);
diff --git a/sys/isa/atrtc.c b/sys/isa/atrtc.c
index f785849faca..652cc0144cd 100644
--- a/sys/isa/atrtc.c
+++ b/sys/isa/atrtc.c
@@ -93,10 +93,6 @@ __FBSDID("$FreeBSD$");
 #include <i386/bios/mca_machdep.h>
 #endif
 
-#ifdef XBOX
-#include <machine/xbox.h>
-#endif
-
 /*
  * 32-bit time_t's can't reach leap years before 1904 or after 2036, so we
  * can use a simple formula for leap years.
@@ -543,11 +539,6 @@ calibrate_clocks(void)
 	return (tot_count);
 
 fail:
-#ifdef XBOX
-	if (arch_i386_is_xbox)
-		timer_freq = 1125000; /* gives ~733.34MHz CPU clock */
-#endif
-
 	if (bootverbose)
 	        printf("failed, using default i8254 clock of %u Hz\n",
 		       timer_freq);