Xubuntu default screen saver: random - permanently blanks screen

[Dave H]

Did a clean install of Xubuntu 11.10 from a USB stick on my Lenovo S10e Netbook (2nd 'new' Hard disk). After all the options left the install to complete, came back 20 minutes later to a blank screen from which I could not recover. Power down and power up, all OK, new install of Xubuntu OK. Left the new install to update, came back 30 minutes later to a blank screen that I could not recover from. Power down and power up, all OK. Looked at the screen saver options, it was set to Random and I noted that only a few screen saver items were installed. changed the screen saver option to 'single' and selected a installed screen saver, screen saver functioned as expected. I concluded the un-recoverable blank screen is caused by the Random screen saver selecting a screen saver that is not installed.