hp Pavillion won't sleep

[Ed Jabbour]

HP Pavillion dv9720us won't be put to sleep.  2GB RAM, 3GB swap.  I've tried 
fooling with Power Manager, with /etc/default acpi-support, and such.  No 
matter what I do, trying sleep only switches the screen to what looks to be 
part of the boot process and I have to ctl-alt-del out.   I've googled so 
much I've gone cross-eyed and really don't remember everything I've tried.  
Any hints or pointers greatly appreciated.