ubuntu 18.04 LTS does not load onboard intel 82G33/G31 graphics controller

[Hanumanth Sastry]

upgraded from Ubuntu 16.04 LTS to 18.04 LTS but graphic display has failed and is extremely slow. $ glxinfo|grep OpenGL gives below output:
OpenGL vendor string: VMware, Inc.
OpenGL renderer string: llvmpipe (LLVM 6.0, 128 bits)
OpenGL core profile version string: 3.3 (Core Profile) Mesa 18.0.5
OpenGL core profile shading language version string: 3.30

$ lshw | grep display gives below output:

*-display UNCLAIMED

Onboard intel graphics controller worked perfectly on 16.04 but failed on upgrading to 18.04

Kindly suggest a workaround to re-enable onboard intel 82G33/G31 Integrated Graphics Controller (rev 10) on ubuntu 18.04 LTS.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: xorg 1:7.7+19ubuntu7.1
Uname: Linux 4.18.5-041805-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.3
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
CurrentDesktop: ubuntu:GNOME
Date: Wed Sep 5 19:02:47 2018
DistUpgraded: Fresh install
DistroCodename: bionic
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes, including running git bisection searches
GraphicsCard:
 Intel Corporation 82G33/G31 Express Integrated Graphics Controller [8086:29c2] (rev 10) (prog-if 00 [VGA controller])
   Subsystem: Gigabyte Technology Co., Ltd 82G33/G31 Express Integrated Graphics Controller [1458:d000]
InstallationDate: Installed on 2015-07-19 (1144 days ago)
InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
MachineType: Gigabyte Technology Co., Ltd. G31M-ES2L
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.18.5-041805-generic root=UUID=8d00030d-c1a2-47fd-8b97-b7813c6e7ef6 ro quiet splash nomodeset vt.handoff=1
Renderer: Software
SourcePackage: xorg
UpgradeStatus: No upgrade log present (probably fresh install)
XorgConf:
 Section "Device"
     Identifier "Intel Graphics"
     Driver "intel"
     Option "AccelMethod" "uxa"
 EndSection
dmi.bios.date: 09/29/2009
dmi.bios.vendor: Award Software International, Inc.
dmi.bios.version: F10
dmi.board.name: G31M-ES2L
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.chassis.type: 3
dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
dmi.modalias: dmi:bvnAwardSoftwareInternational,Inc.:bvrF10:bd09/29/2009:svnGigabyteTechnologyCo.,Ltd.:pnG31M-ES2L:pvr:rvnGigabyteTechnologyCo.,Ltd.:rnG31M-ES2L:rvr:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvr:
dmi.product.name: G31M-ES2L
dmi.sys.vendor: Gigabyte Technology Co., Ltd.
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.91-2
version.libgl1-mesa-dri: libgl1-mesa-dri 18.0.5-0ubuntu0~18.04.1
version.libgl1-mesa-glx: libgl1-mesa-glx 18.0.5-0ubuntu0~18.04.1
version.xserver-xorg-core: xserver-xorg-core 2:1.19.6-1ubuntu4
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:18.0.1-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20171229-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-2

[Daniel van Vugt (vanvugt)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 1727356, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Feel free to continue to report any other bugs you may find.