PC inexplicably going into Sleep mode after Media Center initialized

[tornado1]

I have a 32 bit Windows 7 Lenovo Thinkpad L412.

In the past few weeks I have re-imaged my hd to factory state (as I do often).

After a few days it begins to go into sleep or stand-by mode after being left idle for around 5-10 minutes. It does not turn off, or actually hibernate, it simply goes to the user log-in screen prompting for a password to return to the desktop.

I have no idea why. I am not a noob or anything, I have checked the power options, and power manager and changed all settings for sleep/hibernate/standby to never, including the power plan I am on.

I can find absolutely no reason why it is going to the log-in screen.


HOWEVER, I think it only starts doing this after I have opened and set-up Windows Media Center. After putting my TV tuner in via USB and setting up my TV in windows media (which works fine), the comp begins going to sleep after 5-10 minutes.

It will do this indefinitely, even if I take the PC tuner out or close WMC, or restart.

HELP?! This is unbelievably frustrating I cannot believe I can't figure this out.

 

[Layback Bear]

I have never used such a gadget but I do have a idea. Did this T.V. Tuner come with a program that has settings to put the computer to sleep. Those settings if they are there may be over riding Windows settings.

 

[tornado1]

I have never used such a gadget but I do have a idea. Did this T.V. Tuner come with a program that has settings to put the computer to sleep. Those settings if they are there may be over riding Windows settings.

Thanks for the reply. But, no, only the drivers are installed. The software being used is WMC. Unfortunately, I'm not aware of how WMC could be causing this.

 

[Layback Bear]

I hope I do this right.
1. Start Orb and type Power
2. Power Options
3. Change when computer sleeps
4. Change Advance Power Settings
5. Power Options
6. Multimedia
7. When Sharing Media
8. Select (Prevent Idling to Sleep).

This site may also be of some help understanding USB and Sleep.
http://technet.microsoft.com/en-us/library/cc947756(v=ws.10).aspx