diff --git a/SheepShaver/src/BeOS/main_beos.cpp b/SheepShaver/src/BeOS/main_beos.cpp
index 542e266e..f994510f 100644
--- a/SheepShaver/src/BeOS/main_beos.cpp
+++ b/SheepShaver/src/BeOS/main_beos.cpp
@@ -219,6 +219,7 @@ uint32 DREmulatorAddr;	// Address of DR Emulator
 uint32 PVR;				// Theoretical PVR
 int64 CPUClockSpeed;	// Processor clock speed (Hz)
 int64 BusClockSpeed;	// Bus clock speed (Hz)
+int64 TimebaseSpeed;	// Timebase clock speed (Hz)
 system_info SysInfo;	// System information
 
 static void *sig_stack = NULL;		// Stack for signal handlers
@@ -299,6 +300,7 @@ void SheepShaver::ReadyToRun(void)
 	}
 	CPUClockSpeed = SysInfo.cpu_clock_speed;
 	BusClockSpeed = SysInfo.bus_clock_speed;
+	TimebaseSpeed = BusClockSpeed / 4;
 
 	// Delete old areas
 	area_id old_kernel_area = find_area(KERNEL_AREA_NAME);
diff --git a/SheepShaver/src/Unix/configure.ac b/SheepShaver/src/Unix/configure.ac
index 67a94eab..b3407d94 100644
--- a/SheepShaver/src/Unix/configure.ac
+++ b/SheepShaver/src/Unix/configure.ac
@@ -224,7 +224,7 @@ AC_HEADER_STDC
 AC_HEADER_SYS_WAIT
 AC_CHECK_HEADERS(mach/vm_map.h mach/mach_init.h sys/mman.h)
 AC_CHECK_HEADERS(sys/time.h sys/times.h sys/socket.h)
-AC_CHECK_HEADERS(unistd.h fcntl.h byteswap.h)
+AC_CHECK_HEADERS(unistd.h fcntl.h byteswap.h dirent.h)
 AC_CHECK_HEADERS(linux/if.h, [], [], [
 #if HAVE_SYS_SOCKET_H
 # include <sys/socket.h>
diff --git a/SheepShaver/src/Unix/main_unix.cpp b/SheepShaver/src/Unix/main_unix.cpp
index 2e536918..f8516e1a 100644
--- a/SheepShaver/src/Unix/main_unix.cpp
+++ b/SheepShaver/src/Unix/main_unix.cpp
@@ -127,6 +127,10 @@
 #include "debug.h"
 
 
+#ifdef HAVE_DIRENT_H
+#include <dirent.h>
+#endif
+
 #ifdef USE_SDL
 #include <SDL.h>
 #endif
@@ -275,6 +279,7 @@ uint32 DRCacheAddr;		// Address of DR Cache
 uint32 PVR;				// Theoretical PVR
 int64 CPUClockSpeed;	// Processor clock speed (Hz)
 int64 BusClockSpeed;	// Bus clock speed (Hz)
+int64 TimebaseSpeed;	// Timebase clock speed (Hz)
 
 
 // Global variables
@@ -566,6 +571,7 @@ int main(int argc, char **argv)
 	PVR = 0x00040000;			// Default: 604
 	CPUClockSpeed = 100000000;	// Default: 100MHz
 	BusClockSpeed = 100000000;	// Default: 100MHz
+	TimebaseSpeed =  25000000;	// Default:  25MHz
 #if EMULATED_PPC
 	PVR = 0x000c0000;			// Default: 7400 (with AltiVec)
 #elif defined(__APPLE__) && defined(__MACH__)
@@ -670,6 +676,27 @@ int main(int argc, char **argv)
 			BusClockSpeed = value.l;
 		fclose(proc_file);
 	}
+
+	// Get actual timebase frequency
+	TimebaseSpeed = BusClockSpeed / 4;
+	DIR *cpus_dir;
+	if ((cpus_dir = opendir("/proc/device-tree/cpus")) != NULL) {
+		struct dirent *cpu_entry;
+		while ((cpu_entry = readdir(cpus_dir)) != NULL) {
+			if (strstr(cpu_entry->d_name, "PowerPC,") == cpu_entry->d_name) {
+				char timebase_freq_node[256];
+				sprintf(timebase_freq_node, "/proc/device-tree/cpus/%s/timebase-frequency", cpu_entry->d_name);
+				proc_file = fopen(timebase_freq_node, "r");
+				if (proc_file) {
+					union { uint8 b[4]; uint32 l; } value;
+					if (fread(value.b, sizeof(value), 1, proc_file) == 1)
+						TimebaseSpeed = value.l;
+					fclose(proc_file);
+				}
+			}
+		}
+		closedir(cpus_dir);
+	}
 #endif
 	D(bug("PVR: %08x (assumed)\n", PVR));
 
@@ -954,7 +981,7 @@ int main(int argc, char **argv)
 		kernel_data->v[0xf60 >> 2] = htonl(PVR);
 		kernel_data->v[0xf64 >> 2] = htonl(CPUClockSpeed);			// clock-frequency
 		kernel_data->v[0xf68 >> 2] = htonl(BusClockSpeed);			// bus-frequency
-		kernel_data->v[0xf6c >> 2] = htonl(BusClockSpeed / 4);		// timebase-frequency
+		kernel_data->v[0xf6c >> 2] = htonl(TimebaseSpeed);			// timebase-frequency
 	} else {
 		kernel_data->v[0xc80 >> 2] = htonl(RAMSize);
 		kernel_data->v[0xc84 >> 2] = htonl(RAMSize);
@@ -968,7 +995,7 @@ int main(int argc, char **argv)
 		kernel_data->v[0xf80 >> 2] = htonl(PVR);
 		kernel_data->v[0xf84 >> 2] = htonl(CPUClockSpeed);			// clock-frequency
 		kernel_data->v[0xf88 >> 2] = htonl(BusClockSpeed);			// bus-frequency
-		kernel_data->v[0xf8c >> 2] = htonl(BusClockSpeed / 4);		// timebase-frequency
+		kernel_data->v[0xf8c >> 2] = htonl(TimebaseSpeed);			// timebase-frequency
 	}
 
 	// Initialize extra low memory
diff --git a/SheepShaver/src/include/main.h b/SheepShaver/src/include/main.h
index b2ae6acf..fb8248f1 100644
--- a/SheepShaver/src/include/main.h
+++ b/SheepShaver/src/include/main.h
@@ -28,6 +28,7 @@ extern uint32 BootGlobsAddr;	// Address of BootGlobs structure at top of Mac RAM
 extern uint32 PVR;				// Theoretical PVR
 extern int64 CPUClockSpeed;		// Processor clock speed (Hz)
 extern int64 BusClockSpeed;		// Bus clock speed (Hz)
+extern int64 TimebaseSpeed;		// Timebase clock speed (Hz)
 
 #ifdef __BEOS__
 extern system_info SysInfo;		// System information
diff --git a/SheepShaver/src/kpx_cpu/src/cpu/ppc/ppc-execute.cpp b/SheepShaver/src/kpx_cpu/src/cpu/ppc/ppc-execute.cpp
index bfb9eccb..a7bcac3f 100644
--- a/SheepShaver/src/kpx_cpu/src/cpu/ppc/ppc-execute.cpp
+++ b/SheepShaver/src/kpx_cpu/src/cpu/ppc/ppc-execute.cpp
@@ -1145,7 +1145,7 @@ static inline uint64 get_tb_ticks(void)
 {
 	uint64 ticks;
 #ifdef SHEEPSHAVER
-	const uint32 TBFreq = BusClockSpeed / 4;
+	const uint32 TBFreq = TimebaseSpeed;
 	ticks = muldiv64(GetTicks_usec(), TBFreq, 1000000);
 #else
 	const uint32 TBFreq = 25 * 1000 * 1000; // 25 MHz
diff --git a/SheepShaver/src/name_registry.cpp b/SheepShaver/src/name_registry.cpp
index e50a91a3..2830ad30 100644
--- a/SheepShaver/src/name_registry.cpp
+++ b/SheepShaver/src/name_registry.cpp
@@ -138,7 +138,7 @@ void DoPatchNameRegistry(void)
 			RegistryPropertyCreate(power_pc.ptr(), "clock-frequency", u32.ptr(), 4);
 			u32.set_value(BusClockSpeed);
 			RegistryPropertyCreate(power_pc.ptr(), "bus-frequency", u32.ptr(), 4);
-			u32.set_value(BusClockSpeed / 4);
+			u32.set_value(TimebaseSpeed);
 			RegistryPropertyCreate(power_pc.ptr(), "timebase-frequency", u32.ptr(), 4);
 			u32.set_value(PVR);
 			RegistryPropertyCreate(power_pc.ptr(), "cpu-version", u32.ptr(), 4);