New ethernet connection is only detected when power is plugged in

Seemingly if connecting a wired ethernet connection for the first time after boot, the connection is not detected until/unless the power lead is also plugged in. Once this has happened the ethernet can be plugged and unplugged at will.

1. Boot without power cable plugged in
2. Connect ethernet

Result: No wired connection detected

Wired connection is detected when power cord is plugged in.

Will investigate further.

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: linux-image-3.8.0-9-generic 3.8.0-9.18
ProcVersionSignature: Ubuntu 3.8.0-9.18-generic 3.8.1
Uname: Linux 3.8.0-9-generic x86_64
ApportVersion: 2.9-0ubuntu2
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: jack 2892 F.... pulseaudio
Date: Sun Mar 3 22:20:49 2013
HibernationDevice: RESUME=UUID=55d6b090-34f0-49fc-a6cf-151c69a7d00c
InstallationDate: Installed on 2013-03-02 (1 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Alpha amd64 (20130302)
Lsusb:
 Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
 Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 001 Device 003: ID 04f2:b217 Chicony Electronics Co., Ltd Lenovo Integrated Camera (0.3MP)
MachineType: LENOVO 4290FC1
MarkForUpload: True
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.8.0-9-generic root=UUID=52b028df-e682-407f-bc93-ad35b72125fd ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.8.0-9-generic N/A
 linux-backports-modules-3.8.0-9-generic N/A
 linux-firmware 1.103
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 12/01/2011
dmi.bios.vendor: LENOVO
dmi.bios.version: 8DET56WW (1.26 )
dmi.board.asset.tag: Not Available
dmi.board.name: 4290FC1
dmi.board.vendor: LENOVO
dmi.board.version: Not Available
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Not Available
dmi.modalias: dmi:bvnLENOVO:bvr8DET56WW(1.26):bd12/01/2011:svnLENOVO:pn4290FC1:pvrThinkPadX220:rvnLENOVO:rn4290FC1:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 4290FC1
dmi.product.version: ThinkPad X220
dmi.sys.vendor: LENOVO