A 2002 build Dell laptop with 2 GB RAM and Lubuntu running and providing all the tools and features I need.
I have run 17.10.1 for the last few months with the occasional freeze that leaves no trace in the logs.
The problem seems to occur when the machine is busy, no obvious relationship with any particular process.
The Lubuntu experience has been good and I waited for 18.04.1 as I have no interest in the 'bleeding edge' and a LTS installation seemed the best approach for me.

But, a few hours after a totally clean install of 18.04.1 with all the defaults, a typical freeze.
Had htop running in a terminal and Firefox playing a YouTube video.
I was interested in the apparent low 'busyness' of this latest installation of Firefox.

If the rate of freezes is no worse than before, I will persevere as I can get my work done and the Linux experience is enjoyable.

But, it would be nice if the cause of the freezes could be identified, at least I might then be able to avoid the risk situations.
Previous threads by me on the same subject produced no explanation, and numerous other threads hold no hope.

Any hope of an explanation ?
John.