I'm using a KDE desktop and XFree4 under Mandrake 7.2 with an ATI Mach64 video card and a Hitachi CM751U monitor. With DPMS enabled, the monitor blanks for a few seconds after the timeout period set with xset, but then an "Invalid Scan Freq." message appears from the monitor and the screen shows a garbled video signal. Pressing any key brings back the desktop. In the BIOS (ABIT BH6 rev. 1.1) I have ACPI disabled and APM enabled. I also disabled the BIOS-level power management. I've tried Video Off Methods: "DPMS", "Blank Screen", "V&H Sync + Blank Screen" respectively; nothing fixes the problem. Any suggestions on how to get the screen to stay blank during standby? Many thanks in advance. (P.S. In general I'd like to learn more about how Mandrake supports desktop power management. Can anyone point me in the right direction?)