windows 7 improperly shutsdown and freezes when idle

I have a studio xps 16 - windows 7 64 bit - I downloaded the most recent updatee
when the computer is idle it shutsdown on its own and freezes - he backlight on the keyboard stays lit and no keys work except the power key which I have to hold down. when it starts backup te black screen with the message of improper shutdown displays. then it starts back up. I know this was caused by the installation of HP Pro 8500A officjet printer - I set it up on the network as a wireless printer (did not really know what I was doing). I don' think I will use the internet options avail direclty to the printer. Any solutions? Do I have to unistall and reinstall another way? Please help. I am not that great with computer technology.

I read this before but hoped somebody more knowledgeable would answer but I will offer some "ideas" since as yet no one has responded...

First, make sure your computer has the latest drivers for your printer; that is most important.

Second, from what can find, you DO have a wireless printer but I suppose there is a possibility it has something to do with your network card settings. W7 Computers have sleep/hibernation modes; try going to Control Panel\Device Manager and find your network card and make sure in Power Management that it is set to allow the network card to wake this device.

If it still persists,
If you go to control panel - power options you are supposed to be able to control the period of inactivity required before Sleep and Hibernation occur, by setting your own power specifications in advanced settings. Note, the main purpose is to save battery life on laptops so you really do WANT it sleeping but I know it's frustrating if it won't wake up.