diff --git a/configs/common/Options.py b/configs/common/Options.py
index ff4acbe371..1941875bc2 100644
--- a/configs/common/Options.py
+++ b/configs/common/Options.py
@@ -85,6 +85,10 @@ parser.add_option("--work-end-checkpoint-count", action="store", type="int",
                   help="checkpoint at specified work end count")
 parser.add_option("--work-cpus-checkpoint-count", action="store", type="int",
                   help="checkpoint and exit when active cpu count is reached")
+parser.add_option("--restore-with-cpu", action="store", type="choice",
+                  default="atomic", choices = ["atomic", "timing",
+                                               "detailed", "inorder"],
+                  help = "cpu type for restoring from a checkpoint")
 
 
 # CPU Switching - default switch model goes from a checkpoint
diff --git a/configs/common/Simulation.py b/configs/common/Simulation.py
index 1897fa8cbc..434fe8369c 100644
--- a/configs/common/Simulation.py
+++ b/configs/common/Simulation.py
@@ -60,7 +60,15 @@ def setCPUClass(options):
     test_mem_mode = 'atomic'
 
     if not atomic:
-        if options.checkpoint_restore != None or options.fast_forward:
+        if options.checkpoint_restore != None:
+            if options.restore_with_cpu != options.cpu_type:
+                CPUClass = TmpClass
+                class TmpClass(AtomicSimpleCPU): pass
+            else:
+                if options.restore_with_cpu != "atomic":
+                    test_mem_mode = 'timing'
+
+        elif options.fast_forward:
             CPUClass = TmpClass
             class TmpClass(AtomicSimpleCPU): pass
         else: