Windows 7: Computer won't sleep

I recently installed Windows 7 on my old Asus P4C800-E system. The CPU is a P4 Prescott 3.2 gHz. Video card is a Gigabyte Radeon HD 4650. Sound is USB Turtle Beach Audio Advantage. 2 GB memory.

The system is set to sleep after 30 minutes. It doesn't go to sleep. My keyboard has a sleep button. When I press it, the computer sleeps and them immediately wakes. I've checked that everything has been set correctly. Any ideas why it won't sleep?

Thanks

Power Options and Sleep Mode Problems - Vista Forums

Here, from our extensive library is our tutorial on sleep problems. Works equally well with Windows 7

I had same problem with new install of Win 7. After looking at fixes on sites I went to
the Device Manager and inspected the devices for power management tabs. My Logitech
USB keyboard had a power tab and I unticked the wake up box.( This prevents the start up from keyboard, it seems). The USB mouse also had a wake up box but I left it ticked so that the mouse could be used as the 'wake up' medium. So far sleep is working as planned. The BIOS, Network and many other bits can also cause 'sleeplessness' as well.

Good advice and it is one of the suggestions offered in our tutorial.

I had to change the ACPI setting in the BIOS. After I ran powercfg -a, I saw S1/S3 wasn't active.

I noticed when I ran powercfg lastwake, I saw that it listed "USB Root Hub".

In Device Manager, I turned off allowing the mouse to wake the computer. Pressed the Sleep button on the keyboard, the computer went to sleep and then woke back up again.

Then in Device Manager, I turned off allowing the Keyboard to wake the computer. Pressed the Sleep button, the computer went to sleep and it stayed that way.

I woke it backup and 30 minutes later, it went to sleep, which is what I had it set to in power management.

Thanks

Pentium 4 on 7? Does that work well? I bought an Athlon II 250 and it has twice the performance for a very small price. Just curious.

Why can't you be constructive instead of having something negative to say.

Your point? Its a Pentium 4? They are extinct. That $50 250 would smash right through it.

TY for the rep. Glad that the Tutorial put you on the right track.

The POINT is, you don't have to be an 4ss about it, people come here for help not insults.