Screen goes dark when awake from standby

[StevenD]

Hi, all,
New problem in the last month. When my T60p awakens from standby, sometimes the screen will go dark, starting about 3-4 seconds after it awakens. To fix it, I have to put the laptop into hibernation with Fn-F12, and then wake it up from hibernation, and the problem is then almost always gone until I standby again.
Doesn't happen *every* time I awake from standby, but a good 60%. I tried making sure the external monitor port is off, checked battery settings (it happens plugged-in or on battery), checked msconfig to see if anything strange was running, I restored from an old (but good) system restoration point to see if that might help, basically everything I or Google could think of.
I'm about ready to change settings so closing the lid hibernates instead of stands-by -- wouldn't be the end of the world, but what happened, and what can I try? Thanks!

[dr_st]

Lid close sensor going awry? Doesn't really explain why it only happens following standby and not hibernate / full power down, but who knows?