diff --git a/tests/cli-test-xml/compare/virt-install-panic-default.xml b/tests/cli-test-xml/compare/virt-install-panic-default.xml
index 9b7ddfd5d..b391a2908 100644
--- a/tests/cli-test-xml/compare/virt-install-panic-default.xml
+++ b/tests/cli-test-xml/compare/virt-install-panic-default.xml
@@ -28,8 +28,6 @@
     <emulator>/usr/bin/qemu-kvm</emulator>
     <controller type="usb" index="0" model="none"/>
     <console type="pty"/>
-    <panic model="isa">
-      <address type="isa" iobase="0x505"/>
-    </panic>
+    <panic model="isa"/>
   </devices>
 </domain>
diff --git a/tests/cli-test-xml/compare/virt-install-panic-isa.xml b/tests/cli-test-xml/compare/virt-install-panic-isa.xml
index 9b7ddfd5d..b391a2908 100644
--- a/tests/cli-test-xml/compare/virt-install-panic-isa.xml
+++ b/tests/cli-test-xml/compare/virt-install-panic-isa.xml
@@ -28,8 +28,6 @@
     <emulator>/usr/bin/qemu-kvm</emulator>
     <controller type="usb" index="0" model="none"/>
     <console type="pty"/>
-    <panic model="isa">
-      <address type="isa" iobase="0x505"/>
-    </panic>
+    <panic model="isa"/>
   </devices>
 </domain>
diff --git a/tests/cli-test-xml/compare/virt-install-singleton-config-1.xml b/tests/cli-test-xml/compare/virt-install-singleton-config-1.xml
index 5c38036c8..fc22e0ac6 100644
--- a/tests/cli-test-xml/compare/virt-install-singleton-config-1.xml
+++ b/tests/cli-test-xml/compare/virt-install-singleton-config-1.xml
@@ -63,9 +63,7 @@
     <rng model="virtio">
       <backend model="random">/dev/random</backend>
     </rng>
-    <panic model="isa">
-      <address type="isa" iobase="0x505"/>
-    </panic>
+    <panic model="isa"/>
   </devices>
   <seclabel type="dynamic" model="selinux"/>
   <seclabel type="none" model="dac"/>
diff --git a/virtinst/devicepanic.py b/virtinst/devicepanic.py
index 69f728889..2463b0113 100644
--- a/virtinst/devicepanic.py
+++ b/virtinst/devicepanic.py
@@ -30,7 +30,6 @@ class VirtualPanicDevice(VirtualDevice):
     MODELS = [MODEL_ISA]
 
     ISA_ADDRESS_TYPE = "isa"
-    IOBASE_DEFAULT = "0x505"
 
     @staticmethod
     def get_pretty_model(panic_model):
@@ -48,7 +47,6 @@ class VirtualPanicDevice(VirtualDevice):
                         default_name=MODEL_DEFAULT)
     type = XMLProperty("./address/@type",
                        default_cb=_get_default_address_type)
-    iobase = XMLProperty("./address/@iobase",
-                         default_cb=lambda s: s.IOBASE_DEFAULT)
+    iobase = XMLProperty("./address/@iobase")
 
 VirtualPanicDevice.register_type()