Comment 21 for bug 1390807

Blacklisting dell_laptop fixed the issue for me as well.
Vincent, here's how to do it: open terminal, type:
echo "blacklist dell_laptop" | sudo tee -a /etc/modprobe.d/blacklist.conf
This command appends the words "blacklist dell_laptop" to the "blacklist.conf" file. The dell_laptop driver will not be loaded on startup and will not cause the freeze anymore.