Index: /trunk/src/VBox/Devices/PC/DevAPIC.cpp
===================================================================
--- /trunk/src/VBox/Devices/PC/DevAPIC.cpp	(revision 20038)
+++ /trunk/src/VBox/Devices/PC/DevAPIC.cpp	(revision 20039)
@@ -1318,4 +1318,14 @@
     APICDeviceInfo *dev = PDMINS_2_DATA(pDevIns, APICDeviceInfo *);
     APICState *s = getLapic(dev);
+    if (s->pTimerR3 != pTimer)
+    {
+        for (uint32_t iCpu = 0; iCpu < dev->cCpus; iCpu++)
+        {
+            s = getLapicById(dev, iCpu);
+            if (s->pTimerR3 == pTimer)
+                break;
+        }
+        Assert(s->pTimerR3 == pTimer);
+    }
 
     APIC_LOCK_VOID(dev, VERR_INTERNAL_ERROR);