Computer won't go into proper sleep mode anymore

Hi everyone, I'm have an annoying problem on a computer that otherwise works very well. My laptop no longer properly goes into sleep mode. It still locks the computer but the hard drive and such still run. This is true when I close the laptop lid and when I put it on sleep manually. Help please!

It's an HP dv9700 with Vista Home Premium, by the way.

Hello Pompeius,

Since this just started happening, you might try a System Restore using a restore point dated before this sleep problem.

Hope this helps,
Shawn