Computer wakes up on its own

I've been putting my computer in sleep mode, instead of shutting it down. After engaging sleep mode, I thought my computer was supposed to stay asleep, until I woke it up.
Mine wakes up by itself. I'm usually on my bed, watching TV when it happens. So I'm not bumping my desk, or moving my mouse.
Anybody know what's going on? Are there setting for sleep mode, that regulates how much movement has to be made before the computer wakes up?
I live in a mobile home, and I know they tend to shake and vibrate, more than a house with a solid foundation. Although this one seems rock solid.
If there is settings, like I mentioned above, could it be set so sensitive, that even movement I don't notice wakes it up? Or could it be set up to awake after a certain amount of time?
Thanks in advance.

check the NIC settings (or the BIOS) for WAKE ON LAN - - it should be OFF

Can you, please, tell me where to find these NIC settings, of the BIOS, so I can see if it's turned off or on?

First, look in the device itself, as shown in the attachment.
From the Device->Properties and look at the tabs

For my MSI board w/ AMI BIOS:
Power Management > Wake Up Event Setup > Resume By Onboard LAN (disable/enable)

looks good - - watch for results over night

Here I go again. Not being able to find things, people tell me to look for. I get really frustrated with myself sometimes.
I clicked on the link you gave. Looked like I could find what I needed under Computer Management. Went to CM.
Looked in Device Mgr, Disk management, performance and services. Couldn't find anything about Realtec. DCIe or NIC. Where should I be looking?
Probably should have told you this from the start. My computer is a Lenovo, and I'm running Windows 7 64 bit.
Thanks again, and sorry for being so dense.

Device Manager, then expand Network Adapters. Locate your adapter and go from there.

That was easy Found device mgr, found network adapters, found realtek PCIe clicked power mgr, unchecked allow this device to wake the computer. Thank you very much :0)

I spoke too soon. My computer woke by itself, again last night. So unchecking,"Allow this device to wake the computer," didn't work.

What about turning it off in the BIOS? Does yours have that option?

If the above doesn't work, it might be a program updating its self.

Good one, could be something in the task scheduler.

Here's a couple tricks.
First
This first trick makes the next step easier (avoids typos). It allows you to cut and paste text into command prompt windows with left or right mouse clicks (which I also find very handy). Open a command prompt window.
> Right click the title bar (title bar runs along the top of the window). Select Defaults
> Check Quick Edit then OK
Now you should be able to copy and paste into your command prompt windows with mouse clicks.

Second
Open a command prompt window. Now copy the command below to the clipboard (highlight the text, right click->Copy)

Code:

powercfg -devicequery wake_armed 

then
> Left click to select the command prompt window
> Right click to paste the command text in. Hit return

You should see a list of the devices enabled to wake up your computer. (On my computer, usually includes LAN adapter + keyboard + mouse) see typical output below

Code:

C:\>powercfg -devicequery wake_armed
Logitech HID-Compliant Keyboard
Logitech HID-compliant Cordless Mouse
Broadcom NetLink (TM) Gigabit Ethernet

Go to each device in DevMgr right click Properties->Power Management and disable wake up

Sorry Rabbit01 I don't know how to turn something off in the Bios. What the BIOS is, or if my computer has that option.

You should know me well enough by now. to know that if you say things like "It might be a program updating itself" I'm just going to sit here, and scratch my head, because I barely know what you're talking about.

.Where's the Task scheduler, and whats the something I should be looking for?

No. guarantee.But. If you could tell me what a command prompt window is, and where I would find it. I think I might be able to follow your instructions..

For everyone who is is trying to help me. Thank you. Just so you all wont think I'm completely stupid. A lot of the things you are talking about, I probably know. I just don't know what they are called.
For instance. The window that goes across the top of your browser page. I'm sure has a name. but. To me it's the www. window

Click on your start menu. When it opens click on all programs . Then click on Accessories.Once this opens click command prompt window. Hope this helps.

circusboy01, when I suggested it could be a program updating itsself, that would mean your av updating itsself or any other program you might have thats doing such. Follow the advice given by the others in this thread, I'm sure they're more knowledgeable than I am. I don't know W7 that good,

@circusboy01

No worries. We're all here to help each other out Follow cobalt's instruction to open a command prompt window. The "title bar" is the dark colored bar that runs across the top of a window. The title bar typically tells you what the window is for. Here's one example I found (albeit for an Explorer window)