Screen turns off and on cyclically

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Dragon Queen

New Member
Hi I have a HP a6177c desktop and last nite my daughter went to work on it and the screen was turning off and on, in and out of sleep mode, never going to a workable screen, any ideas or options as to what is going on or fixes would be great. Thanks.
 
Just got done blowing out and double checking connections to the computer and the plugs on the other end. Still same situation. Next step anyone?
 
Exactly when does this sleep cycle occur? Immediately before or after Logon? What tells you it's going to sleep rather than monitor standby? How long is the cycle on/off?

Edit: On re-reading I guess you are referring to monitor sleep. Doesn't it respond to hitting keys or clicking the mouse? Have you tried another monitor?
 
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The sleep cycle occurs immediately on startup and has a 10 sec cycle time, the tower does not go to sleep only the monitor, the power button changes colors. It never gets to any screen other than black, does not respond to the keys or mouse in anyway that I can tell. The other monitor that I have, the plug is not compatible, as the HP monitor has speakers in it, the plug is white and wider than the standard blue and is not all pins one side has slots not pins.
 
Can you connect the monitor to another computer and see if it works properly? Its just so we can rule some things out.
 
Dragon Queen said:
The sleep cycle occurs immediately on startup and has a 10 sec cycle time....
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So you don't even see the POST screens that precede Windows itself starting up? Does the PC make the usual startup sounds (churning of hard drives, flashing hard disk light etc)? Could it be loading Windows as far as the Logon screen but you cannot see it? That would give credence to the monitor being the issue.

If it is stuck on the Logon screen then the mouse and keyboard would be ineffective unless you (blindly and perfectly) duplicated the normal actions to log on. I don't use a logon but if you can remember the sequence eg Enter to select default choice, type in password, hit Enter, you could try that and see if the PC continues churning.

Ruling out the monitor would be first and most certain choice.
 
gamblingman said:
Can you connect the monitor to another computer and see if it works properly? Its just so we can rule some things out.
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Both towers have different monitors ports and dont have any additional ports.

Nanobyte said:
So you don't even see the POST screens that precede Windows itself starting up? Does the PC make the usual startup sounds (churning of hard drives, flashing hard disk light etc)? Could it be loading Windows as far as the Logon screen but you cannot see it? That would give credence to the monitor being the issue.

If it is stuck on the Logon screen then the mouse and keyboard would be ineffective unless you (blindly and perfectly) duplicated the normal actions to log on. I don't use a logon but if you can remember the sequence eg Enter to select default choice, type in password, hit Enter, you could try that and see if the PC continues churning.

Ruling out the monitor would be first and most certain choice.
Click to expand...

The hard drive does kick on as well as the fans, I do not use logon either. The only thing I see on the screen is black or the box that comes up saying monitor is going to sleep, I do know that the tower is not going to sleep with the monitor. This tower does have a tv tuner, but I havent seen any port to use a tv as a screen with it, sides both of my tvs are over 4 yrs old, both are crt tech dont know if either are capable or not to connect.
 
Dragon Queen said:
Both towers have different monitors ports and dont have any additional ports.
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Sorry lost me there. Until now you havent mentioned a second PC and Im not sure you are mentioning one here.

Have you taken the monitor off and plugged it into a different PC?

Better still, grab another monitor and try it on your PC.

Had a HP a few weeks ago, couldnt get the monitor out of sleep mode. It was only on putting on another monitor that I found the problem.

Gary Cantley
 
GaryCantley said:
Sorry lost me there. Until now you havent mentioned a second PC and Im not sure you are mentioning one here.

Have you taken the monitor off and plugged it into a different PC?

Better still, grab another monitor and try it on your PC.

Had a HP a few weeks ago, couldnt get the monitor out of sleep mode. It was only on putting on another monitor that I found the problem.

Gary Cantley
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Sorry Gary I have 3 computers, one is a Dell laptop, one is a old Gateway with a new monitor and the HP. The HP has a 24" HD monitor with speakers on the monitor, the other monitor I have is a plain 19" flatscreen. The monitors do not have the same plug and I can not swap them to test the monitor. If you are saying go buy another moniter to try, it is currently not in the budget. Hope that clears up the confusion. Thanks
Edit: I have had the HP for 2 yrs and has been functional till now.
 
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When someone says try (or grab) another monitor, they don't mean buy a new one. They mean obtain one to try out by whatever means (ask around people you know or see if a local repair shop would do a quick test). You could connect the "other" monitor to your PC or the "other" PC to your monitor.

In your case it may be difficult due to the connection. It's easy with most monitors due to standard DVI or VGA connectors. Your neighbour would probably have one of those. Bad HP!

If your (HP) graphic card and (Gateway) monitor both had VGA you could try that. If the undefined (HP) monitor has VGA input you can probably connect to the Gateway or laptop. From the spec of the HP, there is a motherboard VGA output but it is apparently disabled in favour of the graphic card.

Edit 1: FYI there are generic troubleshooting guides for the w2408 monitor (if that is what you have) and others here and here.

You should check the menus of the monitor to ensure the settings (particularly input if applicable) are as expected.

Edit 2: If you only have one cable connected, are you in fact using HDMI? DVI does not carry audio (unless HP made a real oddball) and would need the audio connected separately. The manual I downloaded shows the monitor probably has DVI, HDMI and VGA inputs. You should definitely check the monitor's "Switch Video Input" on the OSD. The VGA would make testing the monitor quite easy. You can do that using your laptop.
 
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So I got the monitor checked and it is OK, cant get it booted to safe mode either. He did use a vga cable input instead of the dvi I have on the tower. Should I get another dvi cable? Or is it most likely the video card or viral?
Thanks for the help everyone.
 
Try with a new DVI cable as this is easy and cheap. It does sound increasingly like a faulty graphics adaptor to me.

If you have a discrete graphics card (ie a PCI or PCIe or AGP card) take it out and try it in a known working system. If the problem persists in the other system, you know its a faulty card. If you have only onboard (i.e. motherboard graphics), you should borrow a graphics card of any description (that is compatiable with your motherboard) and see if that fixes it. Then you would only need a new graphics card.
 
Ok so I took another moniter and found the vga plug that goes to the mobo on the tower. Pluged it in and still nothing. Do i need to disable the video card for the mobo vga to work? or should it find the moniter on its own?
 
Bigfella, I did read your previous post, my other tower doesn't have a pci slot to fit this graphics card and I don't go to the next city over that often where there is a computer shop to do the testing. I am the only one in my circle of nearby friends that is willing to open up a tower and fiddle and not just take it to a computer shop, so borrowing a card is not available to me. I was attempting to check the card by using onboard graphics, using the vga plug I found hidden under a cover. So that is the reason I asked the last question just trying to rule out things that had been suggested to me by the knowledgable here without having to wait another week or 2 to go to town for parts or for a computer shop to charge me money to check something. Thanks for all the help and hope it continues.
 
In your situation with no equipment to substitute you have limited possibilities. Sometimes you have to take the PC to a repair shop solely because they have bits and pieces laying around that they can put in the PC. Obviously you can't get into the BIOS.

The only possibilities left that I can think of are to remove the graphic card and plug your monitor into the MB VGA. If that fails to boot or display on the monitor, clear the BIOS settings (google "clear bios" for details) and try again. That would reset any video device selection for the boot process. It could put you into as much trouble as you currently have even if it's successful. You would have to redo all the BIOS settings which you probably have no record of.

If you want to eliminate risk and minimize cost, phone repair shops ahead and find one that will check the system on the spot when you arrive with a new video cable.
 
I got the graphics card out and it is currently running startup repair, ya finally got something other than that stupid black screen. However since it is saying attempting repairs to disk now, something else is probably wrong in there correct?
Thanks again for all of the input and I will update when it gets done with whatever and I get back into the OS, (please get back into the OS).
 
Got into the OS and most everything appears to be running. Some of the screen savers won't work, no direct10x without the card. just need to start looking at info to replace it. Thanks all
 
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