First the upgrade appeared to break the the Internet connection while it was in progress, so it failed. I then rebooted several times, attempting to load first the 3-17.x kernel that I had already installed (and it was functioning well), then the 3.16.7 (which did also) and next the default 3.14, all in both normal and safe mode, but my screen went black and didn’t recover, each time.
My monitor is a 19" Panasonic Viera LED (a TV being used as a monitor), which had been working OK until now and is what I am using at the moment from Sparky Linux Ultra Openbox, to write this (which connects the the Internet with no problems).
Since cldx was performing very well before the upgrade I will try reinstalling it without formating the partitions, unless a better suggestion is provided.
Thanks in advance for your comments.
UPDATE - I was unable to reinstall using either of the 2 latest cldx stages burned using unetbootin (they wouldn’t load), BUT - I then logged in without problems to the original 3.14.x kernel in safe mode and completed a system update, so Calculate has returned to full funcionality as my number one system on my main desktop computer.