diff --git a/src/cpu/core_full/load.h b/src/cpu/core_full/load.h
index cd620add..0a3f1ae0 100644
--- a/src/cpu/core_full/load.h
+++ b/src/cpu/core_full/load.h
@@ -502,7 +502,7 @@ l_M_Ed:
 		continue;
 	case D_RDTSC: {
 		if (CPU_ArchitectureType<CPU_ARCHTYPE_PENTIUMSLOW) goto illegalopcode;
-		Bit64s tsc=(Bit64s)(PIC_FullIndex()*(double)CPU_CycleMax);
+		Bit64s tsc=(Bit64s)(PIC_FullIndex()*(double)(CPU_CycleAutoAdjust?70000:CPU_CycleMax));
 		reg_edx=(Bit32u)(tsc>>32);
 		reg_eax=(Bit32u)(tsc&0xffffffff);
 		break;
diff --git a/src/cpu/core_normal/prefix_0f.h b/src/cpu/core_normal/prefix_0f.h
index 84f1b741..38004f1f 100644
--- a/src/cpu/core_normal/prefix_0f.h
+++ b/src/cpu/core_normal/prefix_0f.h
@@ -228,7 +228,8 @@
 	CASE_0F_B(0x31)												/* RDTSC */
 		{
 			if (CPU_ArchitectureType<CPU_ARCHTYPE_PENTIUMSLOW) goto illegal_opcode;
-			Bit64s tsc=(Bit64s)(PIC_FullIndex()*(double)CPU_CycleMax);
+			/* Use a fixed number when in auto cycles mode as else the reported value changes constantly */
+			Bit64s tsc=(Bit64s)(PIC_FullIndex()*(double) (CPU_CycleAutoAdjust?70000:CPU_CycleMax));
 			reg_edx=(Bit32u)(tsc>>32);
 			reg_eax=(Bit32u)(tsc&0xffffffff);
 		}