I have monitor problems.

Ok I let my neice us a LG FLATRON L1511SK
She stopped using it and I picked it back up an dhooked it up to another computer, both use XP.

The monitor goes dark after a few seconds and sometimes I can barely see the screen. I've trying adjusting the menu, auto adjust, and lightview. The monito is approx 18 months old. I've also installed the cd it came with again.

It's very possible the monitor is just dead. I think those have a 3yr warranty on them. Jot down the serial number and model number off the back of the monitor and call LG support directly (or email them - but you'll get more done over the phone. From their site:

"USA customers can email directly to customerservice@lge.com or dial 1-800-243-0000 immediate support."