Luckily I had a 32 GB SanDisk USB 3.0 flash drive on hand (the one that was
farkled by trying to upgrade 15.10 to 16.04), so I installed 15.10 on it
and upgraded. I didn't add any programs, so this is vanilla 15.10. I
followed the instructions at the link you gave and successfully installed
the mainline kernel 4.6-rc6. Restarting, I successfully used the new kernel
to boot into 15.10. I don't have any complex programs other than Mozilla
Firefox to run on this installation, but it seems to be working fine.
Apparently the problem is not in the kernel.

On Tue, Jul 5, 2016 at 6:15 PM, Christopher M. Penalver <
<email address hidden>> wrote:

> Roger Merritt, to further narrow this down, could you please test the
> latest mainline kernel (4.7-rc6) following
> https://wiki.ubuntu.com/Kernel/MainlineBuilds and advise to the results?
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1584284
>
> Title:
>   Ubuntu 16.04 LiveCD does not boot on AMD A10 chip
>
> Status in xorg package in Ubuntu:
>   Incomplete
>
> Bug description:
>   I want to boot a Ubuntu LiveCD of 16.04 on a desktop box with an AMD
> A10-5800K AGP,  Gigabyte FA-42A75M-HD2 motherboard, 8 GB of RAM, and no
> graphics card -- the Radeon HD 7660D graphics are done by the CPU. When I
> try to boot I get an error message, "ERROR: no UMS support in radeon
> module." When I edit the boot command line to add the parameter 'nomodeset'
> I first get an error message, "No UMS support on radeon module," then the
> familiar aubergine background with the ubuntu logo and the five dots below
> it changing from white to red and back again. After twenty or thirty
> seconds the background goes to black, I get the error message "No UMS
> support in radeon module," and the ubuntu logo disappears but the five dots
> continue. After another twenty or thirty seconds of that the screen clears,
> at the top is a line: "ubuntu 16.04 ubuntu LTS tty1," below that the line
> "ubuntu login:" and after a second or less the screen goes black and I
> can't do anything except reboot. I've tried old Live CDs, from 10.10 to
> 15.10, and they all boot fine.
>   ---
>   .tmp.unity.support.test.0:
>
>   ApportVersion: 2.19.1-0ubuntu5
>   Architecture: amd64
>   CompizPlugins: No value set for
> `/apps/compiz-1/general/screen0/options/active_plugins'
>   CompositorRunning: compiz
>   CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
>   CompositorUnredirectFSW: true
>   DistUpgraded: Fresh install
>   DistroCodename: wily
>   DistroRelease: Ubuntu 15.10
>   DistroVariant: ubuntu
>   DkmsStatus: virtualbox, 5.0.14, 4.2.0-36-generic, x86_64: installed
>   ExtraDebuggingInterest: Yes
>   GraphicsCard:
>    Advanced Micro Devices, Inc. [AMD/ATI] Trinity [Radeon HD 7660D]
> [1002:9901] (prog-if 00 [VGA controller])
>      Subsystem: Advanced Micro Devices, Inc. [AMD/ATI] Trinity [Radeon HD
> 7660D] [1002:9901]
>   InstallationDate: Installed on 2016-06-07 (27 days ago)
>   InstallationMedia: Ubuntu 15.10 "Wily Werewolf" - Release amd64
> (20151021)
>   MachineType: Gigabyte Technology Co., Ltd. To be filled by O.E.M.
>   Package: xorg 1:7.7+7ubuntu4
>   PackageArchitecture: amd64
>   ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.2.0-36-generic
> root=UUID=376cfbdb-7508-4e73-9b25-421ca397ab8a ro quiet splash vt.handoff=7
>   ProcVersionSignature: Ubuntu 4.2.0-36.42-generic 4.2.8-ckt8
>   Tags:  wily ubuntu compiz-0.9
>   UdevLog: Error: [Errno 2] No such file or directory: '/var/log/udev'
>   Uname: Linux 4.2.0-36-generic x86_64
>   UpgradeStatus: No upgrade log present (probably fresh install)
>   UserGroups:
>
>   _MarkForUpload: True
>   dmi.bios.date: 03/18/2013
>   dmi.bios.vendor: American Megatrends Inc.
>   dmi.bios.version: F4
>   dmi.board.asset.tag: To be filled by O.E.M.
>   dmi.board.name: F2A75M-HD2
>   dmi.board.vendor: Gigabyte Technology Co., Ltd.
>   dmi.board.version: To be filled by O.E.M.
>   dmi.chassis.asset.tag: To Be Filled By O.E.M.
>   dmi.chassis.type: 3
>   dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
>   dmi.chassis.version: To Be Filled By O.E.M.
>   dmi.modalias:
> dmi:bvnAmericanMegatrendsInc.:bvrF4:bd03/18/2013:svnGigabyteTechnologyCo.,Ltd.:pnTobefilledbyO.E.M.:pvrTobefilledbyO.E.M.:rvnGigabyteTechnologyCo.,Ltd.:rnF2A75M-HD2:rvrTobefilledbyO.E.M.:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvrToBeFilledByO.E.M.:
>   dmi.product.name: To be filled by O.E.M.
>   dmi.product.version: To be filled by O.E.M.
>   dmi.sys.vendor: Gigabyte Technology Co., Ltd.
>   version.compiz: compiz 1:0.9.12.2+15.10.20151202-0ubuntu1
>   version.ia32-libs: ia32-libs N/A
>   version.libdrm2: libdrm2 2.4.64-1
>   version.libgl1-mesa-dri: libgl1-mesa-dri 11.0.2-1ubuntu4
>   version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
>   version.libgl1-mesa-glx: libgl1-mesa-glx 11.0.2-1ubuntu4
>   version.xserver-xorg-core: xserver-xorg-core 2:1.17.2-1ubuntu9.1
>   version.xserver-xorg-input-evdev: xserver-xorg-input-evdev
> 1:2.9.2-1ubuntu1
>   version.xserver-xorg-video-ati: xserver-xorg-video-ati
> 1:7.5.0+git20150819-0ubuntu1
>   version.xserver-xorg-video-intel: xserver-xorg-video-intel
> 2:2.99.917+git20150808-0ubuntu4
>   version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau
> 1:1.0.11-1ubuntu3
>   xserver.bootTime: Tue Jul  5 00:55:16 2016
>   xserver.configfile: default
>   xserver.devices:
>    input        Power Button         KEYBOARD, id 6
>    input        Power Button         KEYBOARD, id 7
>    input        USB Optical Wheel Mouse MOUSE, id 8
>    input        Logitech USB Keyboard KEYBOARD, id 9
>    input        Logitech USB Keyboard KEYBOARD, id 10
>   xserver.errors:
>
>   xserver.logfile: /var/log/Xorg.0.log
>   xserver.version: 2:1.17.2-1ubuntu9.1
>   xserver.video_driver: radeon
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1584284/+subscriptions
>



-- 
Roger