Try pressing the “Windows Key + L” together. This will lock the computer (you will need to know your user name and password to unlock it). It should remain in exactly the same state as you left it even if it goes into standby mode. If the power seems to be off when you return a short press on the power button will return you to the logon screen. Just log in and continue where you left off.
Let’s assume you have the ‘On resume, display welcome screen’ option ticked and your user account is password protected. After leaving your PC temporarily, you can return to the Welcome screen by using ‘Log off, Switch User’ or pressing the Windows key and L. This will keep all your work in memory, but you will need to log in with your password to get at it.

Right Click on desktop, click properties/personalize.
Click Screen saver
Turn off, if off is not available, go under wait and enter zero.
if it reverts the zero into a 1 or does not accept zero, simple enter 9999 into wait, and it shouldn’t go into a black screen as quickly.
(it usually goes into screen saver, and then standby on my computer so that’s what i did and works for me)
http://answers.yahoo.com/question/index;_ylt=AmUfBxHurxJmtJgFyCUCZDvsy6IX;_ylv=3?qid=20090322222400AAGQ65D