suddenly shudown since installed ( new ! ) 10.10

hi
since i made a new install on a new disk partiton ( sda8 ) my system i powerd off randomized ). what you can see in my
log files ( /var/log/* ) is that there you can find mostely at " usb reset". but my previouse installation is on an internal disk.
and the joke is ( oh not it is not a joke ) this don't happen when i run the system in - ubuntu 10.04, windoof or slaris - ups ?
this means for me - it's not a hw-problem.
but look at this message in 10.10 ---> Dec 7 19:03:14 tschang kernel: [ 14.751941] k10temp 0000:00:18.3: unreliable CPU thermal sensor; monitoring disabled

i'm coming from kernel developing too and this message makes me nervös.
tell me if i can you help with more information.
have fun to look at the log-files.
ciao
            richi

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: linux-image-2.6.35-23-generic 2.6.35-23.41
Regression: Yes
Reproducible: Yes
ProcVersionSignature: Ubuntu 2.6.35-23.41-generic 2.6.35.7
Uname: Linux 2.6.35-23-generic x86_64
NonfreeKernelModules: nvidia
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.23.
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: richi 1934 F.... pulseaudio
 /dev/snd/pcmC0D0p: richi 1934 F...m pulseaudio
 /dev/snd/controlC1: richi 1934 F.... pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
 Card hw:0 'NVidia'/'HDA NVidia at 0xfe020000 irq 21'
   Mixer name : 'Nvidia MCP77/78 HDMI'
   Components : 'HDA:10ec0888,10250157,00100202 HDA:10de0002,10de0101,00100000'
   Controls : 37
   Simple ctrls : 20
Card1.Amixer.info:
 Card hw:1 'Exchange'/'Guillemot Corporation Hercules Dualpix Exchange at usb-0000:00:04.1-1, high spe'
   Mixer name : 'USB Mixer'
   Components : 'USB06f8:3005'
   Controls : 2
   Simple ctrls : 1
Card1.Amixer.values:
 Simple mixer control 'Mic',0
   Capabilities: cvolume cvolume-joined cswitch cswitch-joined penum
   Capture channels: Mono
   Limits: Capture 0 - 3328
   Mono: Capture 1644 [49%] [24.42dB] [on]
Date: Tue Dec 7 19:20:07 2010
HibernationDevice: RESUME=UUID=4214ad22-10b7-4420-8560-236b7d800467
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release amd64 (20101007)
MachineType: Acer Aspire X3200
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.35-23-generic root=UUID=19e90b38-579a-4f07-a324-887e96b90ddb ro quiet splash
ProcEnviron:
 PATH=(custom, user)
 LANG=de_DE.utf8
 SHELL=/bin/bash
RelatedPackageVersions: linux-firmware 1.38
SourcePackage: linux
dmi.bios.date: 07/31/2008
dmi.bios.vendor: Phoenix Technologies, LTD
dmi.bios.version: R01-A3
dmi.board.name: WMCP78M
dmi.board.vendor: Acer
dmi.chassis.asset.tag: 0000000000000000000000
dmi.chassis.type: 3
dmi.chassis.vendor: Acer
dmi.modalias: dmi:bvnPhoenixTechnologies,LTD:bvrR01-A3:bd07/31/2008:svnAcer:pnAspireX3200:pvrR01-A3:rvnAcer:rnWMCP78M:rvr:cvnAcer:ct3:cvr:
dmi.product.name: Aspire X3200
dmi.product.version: R01-A3
dmi.sys.vendor: Acer