Hardware is pretty old, it is a Compaq V2000z laptop and it has a Turion 64 ML32, and a Radeon Xpress 200M (RS480M) for integrated graphics. 2GB shared RAM.
In any event, I was pleasantly surprised that KDE seemed to have nice visual effects which didn't seem to tax the CPU too much. However there seems to be a problem whenever power management shuts off the display. When I hit a button or the touchpad to "wake" it, the screen doesn't turn back on. This happened in both the 32 and 64bit versions of Mint 16 KDE. Most of the time I had to power off the computer with the power button and restart, although one time I managed to get Ctl-Alt-Backspace to reload it (at least I think that was what did it... and I might have had the lock on idle disabled).
This does not seem to be related to locking the screen, logging on, or logging off. It seems to be related to turning off the display in power management. Also, it seems that the screen will turn back on correctly when coming out of sleep.
I had seen some old threads where there may have been some bugs with power management and the radeon driver, but none that seemed to have a solution clearly elucidated.
Has anyone had a similar problem, and know a solution? Is this something that might be fixed with an update to KDE?
edit: should have put this in here:
Graphics: Card: Advanced Micro Devices [AMD/ATI] RS480M [Mobility Radeon Xpress 200]
X.Org: 1.14.3 drivers: ati,radeon (unloaded: fbdev,vesa) Resolution: firstname.lastname@example.org
GLX Renderer: Gallium 0.4 on ATI RS480 GLX Version: 2.1 Mesa 9.2.1