I have an HTPC with a Gigabyte GA-MA78GM-S2H board and Athlon 64. I have it connected via HDMI to my TV, and only control it using a remote. However, after about 15 minutes, some sleep mode is activated, and the HDMI signal cuts out until I wiggle/click the mouse.
I have the screensaver disabled in the Screensaver page of the Settings Manager, so it's not that.
My /etc/default/acpi-support reads:
Since commenting out the ACPI_SLEEP, ACPI_HIBERNATE, and USE_DPMS lines, I've restarted acpid and acpi-support, with no effect.
# Comment the next line to disable ACPI suspend to RAM
# Comment the next line to disable suspend to disk
# Change the following to "standby" to use ACPI S1 sleep, rather than S3.
# This will save less power, but may work on more machines
# Add modules to this list to have them removed before suspend and reloaded
# on resume. An example would be MODULES="em8300 yenta_socket"
# Note that network cards and USB controllers will automatically be unloaded
# unless they're listed in MODULES_WHITELIST
# Add modules to this list to leave them in the kernel over suspend/resume
# Should we save and restore state using the VESA BIOS Extensions?
# The file that we use to save the vbestate
# Should we attempt to warm-boot the video hardware on resume?
# Save and restore video state?
# Should we switch the screen off with DPMS on suspend?
# Use Radeontool to switch the screen off? Seems to be needed on some machines
# Uncomment the next line to switch away from X and back again after resume.
# This is needed for some hardware, but should be unnecessary on most.
# Set the following to "platform" if you want to use ACPI to shut down
# your machine on hibernation
# Comment this out to disable screen locking on resume
# Uncomment this line to have DMA disabled before suspend and reenabled
# Uncomment this line to attempt to reset the drive on resume. This seems
# to be needed for some Sonys
# Add services to this list to stop them before suspend and restart them in
# the resume process.
# Restart Infra Red services on resume - off by default as it crashes some
# Spindown time on battery
I'd rather not turn power management off entirely (I still want the ability to turn the machine off and all that), but I don't want to have it going to sleep after 15 minutes.