Gerade ist unverhofft mein Rechner ausgegangen weil die Temperatur etwas zu hoch war. Um diesen Schock vorzeitig zu erkennen helfen ein paar nette Icons im gPanel

recht einfach geht es wenn man lm-senosors und das applet dazu installiert.

sudo apt-get install lm-sensors sensors-applet

dann nach den ansprechbaren Sensoren suchen

sudo sensors-detect

Alle Dialogfenster kann man mit YES beantworten.
Damit die lm-sensors nach dem reboot funktioniert muss noch einiges in die /etc/modules eingetragen werden.

#----cut here----
# I2C adapter drivers
i2c-nforce2
# modprobe unknown adapter NVIDIA i2c adapter
# modprobe unknown adapter NVIDIA i2c adapter
# modprobe unknown adapter NVIDIA i2c adapter
# Chip drivers
w83791d
# no driver for Analog Devices ADT7475 yet
it87
coretemp
#----cut here----

Do you want to add these lines automatically? (yes/NO)
hab ich lieber per Hand gemacht.

sensors

und man kann schon einige Werte sehen.
Nach einem Reboot kann man im Panel -> rechte Maustaste -> Zum panel Hinzufügen->“Hardware Sensor Monitor“ hinzufügen, und auf den eigenen Bedarf anpassen.
acpitz-virtual-0
Adapter: Virtual device
temp1: +40.0°C (crit = +75.0°C)
w83791d-i2c-1-2d
Adapter: SMBus nForce2 adapter at 1c80
in0: +1.26 V (min = +0.00 V, max = +3.06 V)
in1: +1.52 V (min = +0.00 V, max = +3.06 V)
in2: +1.26 V (min = +2.82 V, max = +3.79 V) ALARM
in3: +3.06 V (min = +0.00 V, max = +0.00 V) ALARM
in4: +0.94 V (min = +0.13 V, max = +0.00 V) ALARM
in5: +1.10 V (min = +0.00 V, max = +0.00 V) ALARM
in6: +1.23 V (min = +2.05 V, max = +2.05 V) ALARM
in7: +2.90 V (min = +0.00 V, max = +0.00 V) ALARM
in8: +3.22 V (min = +0.00 V, max = +0.00 V) ALARM
in9: +1.89 V (min = +0.00 V, max = +0.00 V) ALARM
fan1: 0 RPM (min = -1 RPM, div = 8) ALARM
fan2: 0 RPM (min = 42187 RPM, div = 8) ALARM
fan3: 0 RPM (min = -1 RPM, div = 8) ALARM
fan4: 0 RPM (min = 42187 RPM, div = 8) ALARM
fan5: 0 RPM (min = -1 RPM, div = 8) ALARM
temp1: +37.0°C (high = +0.0°C, hyst = +0.0°C) ALARM
temp2: +37.0°C (high = +80.0°C, hyst = +75.0°C)
temp3: +37.0°C (high = +80.0°C, hyst = +75.0°C)
cpu0_vid: +1.419 V
beep_enable:enabled
it8718-isa-0290
Adapter: ISA adapter
in0: +1.22 V (min = +0.00 V, max = +4.08 V)
in1: +3.22 V (min = +0.00 V, max = +4.08 V)
in2: +0.00 V (min = +0.00 V, max = +4.08 V) ALARM
in3: +2.96 V (min = +0.00 V, max = +4.08 V)
in4: +2.91 V (min = +0.00 V, max = +4.08 V)
in5: +0.00 V (min = +0.00 V, max = +4.08 V) ALARM
in6: +0.00 V (min = +0.00 V, max = +4.08 V) ALARM
in7: +2.83 V (min = +0.00 V, max = +4.08 V)
in8: +2.99 V
fan1: 2576 RPM (min = 3245 RPM) ALARM
fan2: 0 RPM (min = 3245 RPM) ALARM
fan3: 0 RPM (min = 0 RPM)
temp1: +34.0°C (low = -1.0°C, high = +127.0°C) sensor = thermal diode
temp2: +42.0°C (low = -1.0°C, high = +127.0°C) sensor = thermistor
temp3: -55.0°C (low = -1.0°C, high = +127.0°C) sensor = thermistor
cpu0_vid: +0.000 V
coretemp-isa-0000
Adapter: ISA adapter
Core 0: +47.0°C (high = +82.0°C, crit = +100.0°C)
coretemp-isa-0001
Adapter: ISA adapter
Core 1: +47.0°C (high = +82.0°C, crit = +100.0°C)
coretemp-isa-0002
Adapter: ISA adapter
Core 2: +42.0°C (high = +82.0°C, crit = +100.0°C)
coretemp-isa-0003
Adapter: ISA adapter
Core 3: +38.0°C (high = +82.0°C, crit = +100.0°C)
Vielen Dank für den Tipp von Easyy-S (www.ubuntufreunde.de)