Powering On When I try to activate the monitor from sleep mode, the monitor just keeps flickering like it's trying to power up but won't. I sent it away once before under warranty and the paperwork came back with it saying it was a power supply problem. The power light is on when it's trying to power on.

press power button in again.
If this doesn't help power down completely by holding in power button for About 40 seconds and then try powering it up with power button again.

Open monitor and look at power supply board for capacitors which are "balooning" or deformed in any way. These look like cylindars on the board. These tend to dry out and make what you are describing occur. Replacing them usually fixes about 80% of the problem you are describing. Those parts run about $0.25 to $0.75 each.. well worth trying, right?

A monitor does not normally save any states such as sleep. If unplugging the monitor from the power source for ten to twenty minutes and re-plugging it in does not fix the problem check and see if the monitor's menu comes up.
Even in sleep mode, the menu for the monitor should show. If it does, try resetting the monitor to factory default settings. If the menu does not show up, then there is an issue with the monitor.

If you use Windows 7, u might have hybrid sleep activated. This is similar to hibernate. When u choose SLEEP, your computer goes to hibernate. Sometimes this hibernate just hangs. You have to reboot computer.
Try pressing the power button for several seconds (10-15). It should power off the laptop.
If not, unplug the charger and remove the battery for a few minutes. Then try to start it up again.

Check the cord and connections for the monitor; this has one wire that must have voltage on it or the monitor goes to sleep, and a broken wire or loose connection will fool it into thinking you are powering down. If this doesn't work try going into power options and setting monitor to never power down.

Hello,
May be the problem comes from the Cpu.
Try to see if the cable from the monitor is firmly connected to the cpu.
One thing more may be the vga card is having problem.
Try to test the screen with another Cpu. Or the cpu with another monitor.
The amber mode is normal as the screen is not receiving signal from the cpu.
At times the memory chip also report this problem (no display or sleep mode)
Do hear any beep sound or any other Errors??
OK try this
Cheers Uttam

old post 2017, 1 year old. Desktop and very old monitor.
This old monitor is CCFL and those fail super easy now.
built in 2005, backlamps are mostly dead now.
VGA cable? or DVI#1 or 2 port connected
the monotor told you PC went to sleep mode
I believe it. I bet the monitor works on any other PC you try, I bet.
so put the PC VISTA in into presentation mode.
(like we do with presentations, or kiosk mode, or using a nice DLP projector in theater)
just one app does this below
or learn to use
control panel, + Power settings, and advanced.
turn off all sleep modes,all hibernate modes.
turn on all wake-on modes, for sure USB ports.
make sure device manager is not showing dead devices (chips) if it is , that means get the missing drivers from Dell, for VISTA. Dell has them on your support page
and we are not DELL.

https://downloads.tomsguide.com/Dont-Sleep,0301-28162.html

Try going to the control panel after clicking on the start button and it will have an icon that says "power options", there will be options there for the sleep functions for the monitor etc.

Try hitting the buttons on the monitor and see if the on screen display would come on. If it does, you can try powering down your computer and then restart. Please let me know how this test goes.

You can google search for an app called NOSLEEP.EXE
It was written by a Symantec employee to keep your screen active regardless of pic settings.
Install and run it. That will verify the issue is with of or monitor
Software is free

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/lisa_52daba487e5b4d53