12.3,update to 4.10.1,network pb, reboot, freeze problems

opensuse 12.3 x86_64 , using networkmanager instead of ifup

i update the 12.3 x86_64 with kde 4.10.1
then
i reboot
then
firefox does not find the proxy. Firefox can connect to a web server with “direct internet”
yawp does not connect to weather server
skype does not connect to skype network
etc.
then
i reboot
then
all network pbs disappears
but fire fox does not find the proxy with “system proxy settings” and firefox finds the proxy using “manual proxy settings”
konqueror finds the proxy
then
i reboot
then
i can reach very rarely kdm even in recovery mode because of automatically reboot or freeze
when i can open a kde session during the opening system reboots or freezes even in recovery mode
one time i had a kernel panic, a software lock up

when i say “system reboots” it’s not a clean reboot but merely a brutal reboot. as if you press the pc reboot button

during previous days testing 12.3
i had only a minor reboot pb : almost each time when i boot, just before displaying kdm :
system freezes
or
system reboots

i suspect the nvidia driver

but at the second reboot no pb

is the “ondemand” power profile activated during boot ?
how to change it to “performance profile” ?