How does a computer "go to sleep?"

My computer is “waking up” all by itself, with no jiggle of the mouse. I set the times to short increments so I could watch it go to screen saver, then go to “sleep.” Then it just “wakes up.”

The weird thing is, this happened on another machine, too. We thought maybe it was the mouse being vibrated by the CPU, which is on the desk. We tested this out by moving the (wireless) mouse to another room. It still “woke up.”

We just bought a new CPU, and it’s doing the same thing! Boggles the mind, it does.

Any ideas?

First and foremost:

Please always provide machine and OS info! It is impossible to provide significant help without this.

I would start with networking: Are any network using programs running in the background? This can include anti-virus programs and many, many others which might periodically auto-update. It can also be a symptom of “wake on lan” when an outside network connection wakes up the machine.

And then a lot of other things…

There’s a BIOS setting for disabling stand-by interrupts from USB port signals, which is usually the issue when the computer will only hibernate intermittently. Some device will send a signal to let Windows know it’s still connected, and Windows will turn itself on in response.

You also might want to check if the network can wake the computer up.

http://www.microsoft.com/whdc/archive/netpm.mspx

Look for Enabling/Disabling Wake-on-LAN.

Ok - sorry. I didn’t know the protocol.

HP Pavilion PC
a6720y
AMD Phenom X4 9550 Quad 4 Processor

6GB Memory
640GB Hard Drive

Wireless LAN
NVIDIA GeForce 9100

Vista Home Premium
64-bit

Kaspersky Anti-virus 2009 - set to run at 1:00 am for updates

Windows Updates are also set to run at 1:00 am

We are seeing this during the day.

Is that enough info? Sorry - I am not very “geeky.”