Noted at http://www.manualslib.com/manual/944605/Samsung-Syncmaster-2494lw.html?page=28 you need to see if the OSD comes up. If it does not, then the monitor is likely failing.
Remember that repair is more than a new monitor.
I had most of a question typed but it just disappeared.
In a nutshell..I am asking about a monitor that sometimes won't come back on after it has been idle following use. SAamsung color monitor Model 2494LW; Lenovo
desktop, Windows 7 Home Premium Service Pack 1; 64 bit operating system; Logitech wireless keyboard. After use, the screen will go black but usually come back on when wanted. Three or four times lately it has not come on, so I have shut the whole unit off and rebooted. Then it comes back on. The question is this: does the problem seem to be monitor or PC related?
thanks for any advice .....