I am replacing a very good and loyal T42P. I was looking for a smaller machine and longer battery life.
HEAT
To my surprise my X100e gets extremely hot every time I use it. Starting from 65°C (normal) to over 83°C degrees C. I cannot use it over my lap because of the extreme heat.
It used to shut down every once in a while due to the heat as a BIOS security measure. All that went away after installing TPFcontrol. TPFC manages the fan much better than BIOS, so it doesn't turn off anymore. Hoewever fan is almost on every time.
Battery Lifetime
Out of the box, the battery lifetime was really short. I formatted the X100e using Rescue and Recovery and suddenly the lifetime of the battery improved big time.
However it doesn't go any longer than 3 1/2 hours. I was expecting a lot more -the reviews are not totally fair saying 4 or 5 hours-. You can get over 4 hours working with a non-resource intensive application running, the lowest screen brightness and setting the power mode to high energy savings.
Conclusion
I was expecting a lot more of this machine. I have bee trying to get the good side of it. I can stand the short battery lifetime.
But the heat... the heat is terrible. It is amazing that I have to install an additional piece of software (TPFC) in order to avoid sudden turns off when the temperature is so high that the Bios has to shut it down as precaution.
Some posts in forums talk about installing another software to manipulate the Processor Speed to prevent high temperatures. I cannot believe that a regular user needs to go further than the usual preinstalled software to fix something that was designed wrong from the beginning.
At this point I am very frustrated with my X100e. I will probably replace it for a X201. But I am also afraid about the heat in the X201.
However let's talk about some Pros:
Points in favor: the design, the keyboard -although the scroll lock key is missing-. The trackpoint -a feature I love in a laptop, too bad very few manufacturers build them in their laptops-.
I am glad some of you like your X100e. I don't.






