Dell inspirion 8600 backlight

[Ron Freidel]

I am wondering if anyone knows how to turn off the display on a Dell
inspirion 8600 when it goes into suspend mode, or if not that then just
turning off the backlight as in dpms.

The only thing I have found is if I do a 

sysctl hw.acpi.video.crt0.active=1

and then

sysctl hw.acpi.video.lcd0.active=0

that turns off the display completely, but it is difficult to get it to
turn back on, plus the video card is still active so there is no power
saving.

Am currently running 6.0-CURRENT, built today, but I find the same
thing on 5.3, and 5.4 pre.

Thanks in advance.