My computer locked up in screen saver mode. I couldn't "CTL ALT DEL" so I pushed the CPU power button and it finally turned off after holding it for about 5 seconds. Now, every time I try to turn on the computer, my monitor displays the message saying "Warning - PC entering power saving mode". I don't know what to do. HP Pavillion a500n with Windows XP. Anybody think they can help me out?

Try booting into Safe Mode by repeatedly tapping the F8 key after your BIOS POST but before Windows starts.

Then check your Power Settings via start > Control Panel > Display > Screen Saver > Monitor Power

Thanks for replying. Unfortunately, when I turn on the computer, the only thing that happens is the Warning message displays that says the PC is entering power saving mode. It doesn't seem to be reboot-able. It won't accept anything from the keyboard.

any new hardware or software that may have caused this? whats the pc specs also? this will help target the problem

No new hardware or software. The only thing I've done recently to the computer is update the Virus software through SBC Yahoo DSL. It prompted me to uninstall my old version of McAfee (which I hadn't used in more than 1.5 yrs). I completed the uninstall and the updating of SBC's virus software and the computer was operating normally. A few hours later the computer froze and I was unable to reboot it. I had to hold the power button for several seconds to get the computer to power down. Then when I tried to start the computer again, I only received the warning message about the PC entering into pwer saving mode. I've had no luck with anything when I try to power on the computer. The CPU is an hp pavilion a500n, approx. 2 yrs old, Windows XP, SBC DSL with Linksys wireless broadband router for laptops. The monitor is an hp pavilion f1503 flat panel. Did I leave anything important out? Any help is greatly appreciated.

pavilion a500n

http://h10025.www1.hp.com/ewfrf/wc/p...&lang=en&cc=us

HP and Compaq Desktop PCs - Performing an HP System Recovery in Windows XP

http://h10025.www1.hp.com/ewfrf/wc/d...cname=bph07145

On hind sight the above would require:

1. A Bootable Recovery Disk

2. Your BIOS set to boot the CD prior to the HDD

Also:

HP and Compaq Desktop PCs - Resolving Startup Problems

http://h10025.www1.hp.com/ewfrf/wc/d...cname=bph07173

Thanks for the references. Unfortunately, still, my CPU seems to not even be booting up at all, so it doesn't accept any commands from the keyboard. As soon as I push the power button on, the monitor displays the Warning-PC entering Standby mode message. This is done immediately, before the computer has time to go through any type of booting up, etc. I've tried typing Esc, F1, F8, F10, all to no avail. I've put the system recovery disc into the CD Rom drive, but again, no response from the computer as it doesn't seem to have ever gotten out of standby mode in order to shut down, reboot, etc. I do hear the fan running when I power on, the light comes on, but no beeps. I tested the monitor just in case that was the problem. It displays the screen images from my laptop when I connected it to my laptop, but when I still have it connected to the laptop and hit Fn F7 keys to switch the screen display back to the laptop only, the same warning message (Warning-PC entering Power Saving Mode) still appears on the monitor (and it's not even connected to the PC). Any other suggestions, or am I just out of luck?

I would open it up and clear the CMOS.

Are you familiar with this?

Basically unplug the computer > open the case > remove the motherboard battery

Look in the battery vicinity for a 3 pin jumper most likely labeled JBAT

If found move the sleeve from 1&2 to 2&3 and wait a few minutes.

Then replace the sleeve to 1&2 and replace the battery and then try to boot.

This should reset all the motherboard settings.

Found this re: the monitor:

http://h10025.www1.hp.com/ewfrf/wc/d...cname=bph04760

Step 7: Disabling power settings in BIOS
If Windows was recently upgraded, Windows might be starting up into a Power Saving state and producing the blank screen before it loads. After Windows loads (about 2 minutes after turning on the PC), press the power button briefly or press the Suspend key on the keyboard to see if the PC comes out of a suspended state. If the PC opens into a suspended state every time the PC is started, use the following steps to disable Power Savings in the BIOS:
Turn on the computer and press the F1 key repeatedly when the first screen appears until Entering Setup ... displays.
In the Setup screen, press the Right Arrow key and select Power.
Press the Down Arrow key to select and configure one of the following items depending on what appears on your screen:
Power Savings, APM, or Advanced Power Management - select Disabled and press the F10 key to save the settings and Exit.
APIC Interrupt Routing - If the PC is using Windows XP and this setting is disabled, select enabled and press F10 to save the settings and exit. Let Windows restart and set your power preferences from within Windows.
If Windows still does not appear or you are unable to use the power options in Windows, find and download the latest BIOS update if one is available for your PC.
Reset the APIC Interrupt back to its previous setting if problems occur.
If changing the power setting does not work, this issue is probably caused by faulty hardware - either the video hardware on the PC (if the monitor works on another PC) or a defective monitor (the monitor does not work on another PC). The defective hardware should be replaced or serviced.
NOTE: If you are experiencing problems with an LCD flat panel display, there are more steps that you can use to resolve your problem, if it is still occurring. Please refer to the HP support document Flat Panel Monitor Is Blank after Starting the Computer, or Power Adapter Appears to be Missing (in English).