gs_allen
asked on
Computer won't turn on
This problem started Saturday afternoon. Was working great prior to this day. When the front power switch is pressed nothing happens. When power supply switch is cycled off and then on the computer powers up for about 3 seconds and then shuts down. (stays on just long enough to hear the hard drive spin up and verify that both fans are working)I have tried a new power supply as well as a new power switch. Same thing happens even if there is no power switch connected.I have also changed the power cord and used a different outlet. Video card, hard drive, & monitor have been swapped with known working units. The same is true for the keyboard and mouse. Can't check the bios setup as it doesn't stay powered up long enough. Would this be a motherboard problem or CPU? The computer is as follows:
ECS P4S5A M/B with Onboard sound and Lan
P4 1.5 CPU
256 MB PC133 SDRAM
Maxtor 40GB 7200rpm Hard Drive
LG 24X CDRW
Panasonic Floppy
Nvidia Geforce2 MX400 32MB Video
300W Power Supply (existing unit)
400W Power Supply (New unit for testing with)
All swapped out parts work pefectly in my older PIII machine.
ECS P4S5A M/B with Onboard sound and Lan
P4 1.5 CPU
256 MB PC133 SDRAM
Maxtor 40GB 7200rpm Hard Drive
LG 24X CDRW
Panasonic Floppy
Nvidia Geforce2 MX400 32MB Video
300W Power Supply (existing unit)
400W Power Supply (New unit for testing with)
All swapped out parts work pefectly in my older PIII machine.
gs,,,
Try this,,,,remove all the peripherals from the computer with the exception of video card (connected to monitor, of course), cpu, and memory. When you power up the system it should the normal POST routine and give you a Keyboard not found error Press F1 to continue or Del to enter setup. Of course, you cannot do any of the above without a keyboard. Install KB and try again. Note: Sometimes mainboards will not start without a keyboard. If the system starts up, then install one component at a time until you find the offending part. If the system does not start with all components removed and since you have tried a known good vid card, then the problem lies in three items: CPU, Memory, or Mainboard (use the procedure outlined by Wakeup).
Try this,,,,remove all the peripherals from the computer with the exception of video card (connected to monitor, of course), cpu, and memory. When you power up the system it should the normal POST routine and give you a Keyboard not found error Press F1 to continue or Del to enter setup. Of course, you cannot do any of the above without a keyboard. Install KB and try again. Note: Sometimes mainboards will not start without a keyboard. If the system starts up, then install one component at a time until you find the offending part. If the system does not start with all components removed and since you have tried a known good vid card, then the problem lies in three items: CPU, Memory, or Mainboard (use the procedure outlined by Wakeup).
i'd like to add a comment to baddog and wakeup's. If you follow their procedure and still nothing then try bench building the board. BEnch building means you physically remove the board form the case and lay it on a table (a wooden table, or nonconducting surfce) and literally try the machine while on a table, if it works fine--you have a short somewheres...chekc all your risers! I've come across this a few times
My current guess is that the motherboard is shorting to the case. Similar to PublicFatality's suggestion. Do you get any POST beep code errors?
Allen,
Have you made any changes in your bios lately? If so I would suggest to try clearing your bios settings. In some cases settings in bios can prevent a pc from booting. The best way to do this is by switching a jumper on your motherboard(you will most likely need to look in your motherboard manual to find the right one), it is usualy near the bios chip. If you can't find the right jumper, you can always remove the battery worse case scenario. You will then need to setup the bios assuming this solves your problem.
Have you made any changes in your bios lately? If so I would suggest to try clearing your bios settings. In some cases settings in bios can prevent a pc from booting. The best way to do this is by switching a jumper on your motherboard(you will most likely need to look in your motherboard manual to find the right one), it is usualy near the bios chip. If you can't find the right jumper, you can always remove the battery worse case scenario. You will then need to setup the bios assuming this solves your problem.
And while you've got it on the bench with min components test the bios battery with a voltmeter.
have a CLOSE look at the mobo.......you will see lots of smallish round cylinders with possibly little 'cross' like things marked in the tops ......these are capacitors.....look VERY closely at them ALL and if you see any that are sorta .....bulging.....then it's a certainty that they haev died........replacing these will be necessary then your mobo MAY work.......
ASKER
Thanks for all the suggestions. Have swapped out the ram and completed the bench test with no success. Clearing the bios made now difference as well. All my spare parts are now used up and I now have to decide which one to go out and buy, a new board or a new cpu. Anybody favor one over the other????
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As stated earlier go with the motherboard.
Before you buy anything, try a different fan on the CPUFAN header - some motherboards will shutdown immediately if they dont detect a signal from the fan on that header.
covenant, good point
hmmm....i dont think it is the fan header. Because he says this "...and verify that both fans are working..."
so if the fans are working...then it is something else. USually when the fan headers go out or the fans dont spin you get an alarm sound. Depending on the motherboard of course. But hey i could be wrong. YOu can try a different fan. I just dont think that is the issue.
so if the fans are working...then it is something else. USually when the fan headers go out or the fans dont spin you get an alarm sound. Depending on the motherboard of course. But hey i could be wrong. YOu can try a different fan. I just dont think that is the issue.
Did you check those capacitors ?
Remove the motherboard from the case. Place it on a non-conductive surface, and retest, preferably with every card except video removed. Let us know the result. As I mentioned before, sometimes the board shorts to the case.
ASKER
Thank you all for the help. It was the motherboard. New Gigabyte board up and running with no problems.
Hmmmm....Why did you go with his answer for the motherboard? I thought i already said it was the motherboard?
In my first comments. And I even explained how to go about finding out for sure?
In my first comments. And I even explained how to go about finding out for sure?
wake up, look under misc
i'm sorry i ment to give you some points but i only have 10 and can't post a vlaue of 5...
Sigh.....No big deal...I dont really need the points. Just that I had the question licked on my first post. hehe
f you have another memory stick to test I would try that first since it is easy to replace ram. IF that doesnt work then try the CPU. IF that still doesnt work, most likely it is the Motherboard.