I had a regular hang up problem with Mepis 8.0 on my old Dell laptop, so when the next version 8.5 got released I gave it a try. Installation went through smoothly and the previous hang up problem seemed to be resolved. The only inconvenience with the new Mepis was that the display GUI option to install an ATI driver was stripped out.
Mepis has a web-page describing how to Install ATI driver. Starting with Mepis 8.5, it's recommended to use the sgfxi script which I followed.
Just for the record here are some screen-shots from the installation: