diff --git a/src/cpu/o3/alpha/cpu_builder.cc b/src/cpu/o3/alpha/cpu_builder.cc
index b1e141ff4..8190256fb 100644
--- a/src/cpu/o3/alpha/cpu_builder.cc
+++ b/src/cpu/o3/alpha/cpu_builder.cc
@@ -31,21 +31,21 @@
 #include <string>
 
 #include "cpu/base.hh"
-#include "cpu/o3/alpha_cpu.hh"
-#include "cpu/o3/alpha_impl.hh"
-#include "cpu/o3/alpha_params.hh"
+#include "cpu/o3/alpha/cpu.hh"
+#include "cpu/o3/alpha/impl.hh"
+#include "cpu/o3/alpha/params.hh"
 #include "cpu/o3/fu_pool.hh"
 #include "sim/builder.hh"
 
-class DerivAlphaO3CPU : public AlphaO3CPU<AlphaSimpleImpl>
+class DerivO3CPU : public AlphaO3CPU<AlphaSimpleImpl>
 {
   public:
-    DerivAlphaO3CPU(AlphaSimpleParams *p)
+    DerivO3CPU(AlphaSimpleParams *p)
         : AlphaO3CPU<AlphaSimpleImpl>(p)
     { }
 };
 
-BEGIN_DECLARE_SIM_OBJECT_PARAMS(DerivAlphaO3CPU)
+BEGIN_DECLARE_SIM_OBJECT_PARAMS(DerivO3CPU)
 
     Param<int> clock;
     Param<int> numThreads;
@@ -144,9 +144,9 @@ Param<bool> defer_registration;
 Param<bool> function_trace;
 Param<Tick> function_trace_start;
 
-END_DECLARE_SIM_OBJECT_PARAMS(DerivAlphaO3CPU)
+END_DECLARE_SIM_OBJECT_PARAMS(DerivO3CPU)
 
-BEGIN_INIT_SIM_OBJECT_PARAMS(DerivAlphaO3CPU)
+BEGIN_INIT_SIM_OBJECT_PARAMS(DerivO3CPU)
 
     INIT_PARAM(clock, "clock speed"),
     INIT_PARAM(numThreads, "number of HW thread contexts"),
@@ -261,11 +261,11 @@ BEGIN_INIT_SIM_OBJECT_PARAMS(DerivAlphaO3CPU)
     INIT_PARAM(function_trace, "Enable function trace"),
     INIT_PARAM(function_trace_start, "Cycle to start function trace")
 
-END_INIT_SIM_OBJECT_PARAMS(DerivAlphaO3CPU)
+END_INIT_SIM_OBJECT_PARAMS(DerivO3CPU)
 
-CREATE_SIM_OBJECT(DerivAlphaO3CPU)
+CREATE_SIM_OBJECT(DerivO3CPU)
 {
-    DerivAlphaO3CPU *cpu;
+    DerivO3CPU *cpu;
 
 #if FULL_SYSTEM
     // Full-system only supports a single thread for the moment.
@@ -386,10 +386,10 @@ CREATE_SIM_OBJECT(DerivAlphaO3CPU)
     params->functionTrace = function_trace;
     params->functionTraceStart = function_trace_start;
 
-    cpu = new DerivAlphaO3CPU(params);
+    cpu = new DerivO3CPU(params);
 
     return cpu;
 }
 
-REGISTER_SIM_OBJECT("DerivAlphaO3CPU", DerivAlphaO3CPU)
+REGISTER_SIM_OBJECT("DerivO3CPU", DerivO3CPU)
 
diff --git a/src/cpu/o3/cpu.cc b/src/cpu/o3/cpu.cc
index 87fee8361..7ed17a91e 100644
--- a/src/cpu/o3/cpu.cc
+++ b/src/cpu/o3/cpu.cc
@@ -85,6 +85,35 @@ FullO3CPU<Impl>::TickEvent::description()
     return "FullO3CPU tick event";
 }
 
+template <class Impl>
+FullO3CPU<Impl>::ActivateThreadEvent::ActivateThreadEvent()
+    : Event(&mainEventQueue, CPU_Tick_Pri)
+{
+}
+
+template <class Impl>
+void
+FullO3CPU<Impl>::ActivateThreadEvent::init(int thread_num,
+                                           FullO3CPU<Impl> *thread_cpu)
+{
+    tid = thread_num;
+    cpu = thread_cpu;
+}
+
+template <class Impl>
+void
+FullO3CPU<Impl>::ActivateThreadEvent::process()
+{
+    cpu->activateThread(tid);
+}
+
+template <class Impl>
+const char *
+FullO3CPU<Impl>::ActivateThreadEvent::description()
+{
+    return "FullO3CPU \"Activate Thread\" event";
+}
+
 template <class Impl>
 FullO3CPU<Impl>::FullO3CPU(Params *params)
     : BaseO3CPU(params),
@@ -257,6 +286,8 @@ FullO3CPU<Impl>::FullO3CPU(Params *params)
 
     lastRunningCycle = curTick;
 
+    lastActivatedCycle = -1;
+
     contextSwitch = false;
 }
 
@@ -574,31 +605,45 @@ FullO3CPU<Impl>::activateWhenReady(int tid)
 
 template <class Impl>
 void
-FullO3CPU<Impl>::activateContext(int tid, int delay)
+FullO3CPU<Impl>::activateThread(unsigned int tid)
 {
-    // Needs to set each stage to running as well.
     list<unsigned>::iterator isActive = find(
         activeThreads.begin(), activeThreads.end(), tid);
 
     if (isActive == activeThreads.end()) {
-        //May Need to Re-code this if the delay variable is the
-        //delay needed for thread to activate
-        DPRINTF(O3CPU, "Adding Thread %i to active threads list\n",
+        DPRINTF(O3CPU, "[tid:%i]: Adding to active threads list\n",
                 tid);
 
         activeThreads.push_back(tid);
     }
+}
 
-    assert(_status == Idle || _status == SwitchedOut);
 
-    scheduleTickEvent(delay);
+template <class Impl>
+void
+FullO3CPU<Impl>::activateContext(int tid, int delay)
+{
+    // Needs to set each stage to running as well.
+    if (delay){
+        DPRINTF(O3CPU, "[tid:%i]: Scheduling thread context to activate "
+                "on cycle %d\n", tid, curTick + cycles(delay));
+        scheduleActivateThreadEvent(tid, delay);
+    } else {
+        activateThread(tid);
+    }
 
-    // Be sure to signal that there's some activity so the CPU doesn't
-    // deschedule itself.
-    activityRec.activity();
-    fetch.wakeFromQuiesce();
+    if(lastActivatedCycle < curTick) {
+        scheduleTickEvent(delay);
 
-    _status = Running;
+        // Be sure to signal that there's some activity so the CPU doesn't
+        // deschedule itself.
+        activityRec.activity();
+        fetch.wakeFromQuiesce();
+
+        lastActivatedCycle = curTick;
+
+        _status = Running;
+    }
 }
 
 template <class Impl>
diff --git a/src/cpu/o3/cpu.hh b/src/cpu/o3/cpu.hh
index 9565bbe4f..2a9ecff4e 100644
--- a/src/cpu/o3/cpu.hh
+++ b/src/cpu/o3/cpu.hh
@@ -102,6 +102,7 @@ class FullO3CPU : public BaseO3CPU
     typedef typename std::list<DynInstPtr>::iterator ListIt;
 
     friend class O3ThreadContext<Impl>;
+
   public:
     enum Status {
         Running,
@@ -114,6 +115,9 @@ class FullO3CPU : public BaseO3CPU
     /** Overall CPU status. */
     Status _status;
 
+    /** Per-thread status in CPU, used for SMT.  */
+    Status _threadStatus[Impl::MaxThreads];
+
   private:
     class TickEvent : public Event
     {
@@ -150,6 +154,49 @@ class FullO3CPU : public BaseO3CPU
             tickEvent.squash();
     }
 
+    class ActivateThreadEvent : public Event
+    {
+      private:
+        /** Number of Thread to Activate */
+        int tid;
+
+        /** Pointer to the CPU. */
+        FullO3CPU<Impl> *cpu;
+
+      public:
+        /** Constructs the event. */
+        ActivateThreadEvent();
+
+        /** Initialize Event */
+        void init(int thread_num, FullO3CPU<Impl> *thread_cpu);
+
+        /** Processes the event, calling activateThread() on the CPU. */
+        void process();
+
+        /** Returns the description of the event. */
+        const char *description();
+    };
+
+    /** Schedule thread to activate , regardless of its current state. */
+    void scheduleActivateThreadEvent(int tid, int delay)
+    {
+        // Schedule thread to activate, regardless of its current state.
+        if (activateThreadEvent[tid].squashed())
+            activateThreadEvent[tid].reschedule(curTick + cycles(delay));
+        else if (!activateThreadEvent[tid].scheduled())
+            activateThreadEvent[tid].schedule(curTick + cycles(delay));
+    }
+
+    /** Unschedule actiavte thread event, regardless of its current state. */
+    void unscheduleActivateThreadEvent(int tid)
+    {
+        if (activateThreadEvent[tid].scheduled())
+            activateThreadEvent[tid].squash();
+    }
+
+    /** The tick event used for scheduling CPU ticks. */
+    ActivateThreadEvent activateThreadEvent[Impl::MaxThreads];
+
   public:
     /** Constructs a CPU with the given parameters. */
     FullO3CPU(Params *params);
@@ -167,6 +214,9 @@ class FullO3CPU : public BaseO3CPU
     /** Initialize the CPU */
     void init();
 
+    /** Add Thread to Active Threads List */
+    void activateThread(unsigned int tid);
+
     /** Setup CPU to insert a thread's context */
     void insertThread(unsigned tid);
 
@@ -522,6 +572,9 @@ class FullO3CPU : public BaseO3CPU
     /** The cycle that the CPU was last running, used for statistics. */
     Tick lastRunningCycle;
 
+    /** The cycle that the CPU was last activated by a new thread*/
+    Tick lastActivatedCycle;
+
     /** Number of Threads CPU can process */
     unsigned numThreads;