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WolverineLogan

Programmer
Oct 9, 2001
29
ZA
After replacing a faulty PSU on my PC. My monitor doesn't start or display anything. The cdrom, floppy drive and HDD powers up when i start the PC but not the Monitor. I tried a different display card but still nothing appears.

Could there be a problem with my processor or RAM ??
Desperately need to get the PC back on line...
 
The CPU wasn't faulty. The PC wasn't switching on.
Power Supply Unit packed up. The power button on the PC gave in then started switching on the PC by the main.
One day it just never started up again.

I replaced the Power Supply and like i said before power is now coming through except that there's no display on the monitor / monitor not powering up
 
WolverineLogan, there is a possibility that the bad PSU damaged something else, such as the mobo or hard drive. Do the keyboard lights come on? You'll probably have to eliminate things one item at a time.

Jim

Please come back and let us know if your
problem is fixed and what fixed it!! [thumbsup2]
 
The keyboard lights, HDD light, Cdrom light all go on when powered up.
The HDD light however stays on and doesn't flicker at all
 
A couple of things spring to mind;
1. That the monitor is broken - unplug it from the system, does it give the "No Signal" message? - If it does it's OK.
2. That the graphics port has been blown by the Faulty PSU - Out on a limb now - get hold of a PCI graphics card and try that. If that gets a signal through then it is certain to be the AGP port that's blown.

Regards. Running a PC without backups is like driving a car without a seatbealt. Your knack'ed when you crash!
 
The monitor is working properly.
I tried changing graphics cards but still no power coming through.
 
Just for clarification;
the card you "changed", was it a different interface or was it placed in a different PCI slot?

Replacing an AGP card with an AGP card or a PCI card with a PCI card wouldn't resolve anything.

Regards. Running a PC without backups is like driving a car without a seatbealt. Your knack'ed when you crash!
 
Your problem may have included more than just the power supply. Look at the capacitors (the tall barrel shaped things) on the motherboard. See if they are crowned. This
tip I got from Gargouille and it has been the culprit on
several occasions with the same symptoms as yours. Thank You
Gargouille!!
 
Hi WLogan:
I don't even know where I was when I read your post...obviously not far enough into the 1st cup of coffee with both eyes wide open...LOL
There's a part of your story that has me wondering: you say the power switch on the box was bad. Have you tried shorting across the leads (very carefully) where the switch connects to the motherboard (with the machine at full rest, powered down)?
It should start it up...and if it doesn't there's more than the case switch going out involved...most likely the motherboard is bad.

I'm taking what you're saying as meaning there's no screen in the POST either, in which case you really need to retreat to just the CPU, RAM, video card and monitor hooked up, unhooking power and IO cables from all the other drives and try it.
The machine should boot to the BIOS in this stage and if not, try removing the video card and trying again. No beeps would indicate probably the motherboard suspect.
There is also a chance your new PS is faulty. Testing it with a meter may confirm it.
 
Hi mainegeek,
Glad you were able to use something offered...and thanks for the feedback.
I got the nooz this was happening when a friend's computer motherboard was going bad...her parts warranty was still active but not the labor part, so she was gonna' have to install the motherboard in the computer and asked me to do it. The 1 I took out had obvious rounded (to the point of almost bursting) capacitors and after I got looking around on the net found lots of boards have this problem.
 
Gargouille,
I had one that I was working on for a while. It took
about 4 or 5 starts to get the thing to boot. Once it was running it was ok. It would power back on again if only off for a minute or two. If I left it off for an hour it would reqiure several starts to get it to boot again. When I opened a large program I could hear a "Hissing Sound".
After reading one of your responses on another post I tried
what you had recommended to them. Three capacitors near the
atx power connector on the mobo where "crowned". One was split at the top and the "Hissing" was actually coming from the split. It sounded like letting air out of a tire. I had
already tested the PS with a tester and all was will. This is an "Excellant Tip" as it makes for a quick and easy Visual Check before moving on to other components for testing. This is saving me alot of time trouble shooting.
I have been faithfully following about a dozen of the regular Tipsters,including you, and I have learned alot more because of it.

Thank You Again.
 
Hi again, mainegeek:
I also follow MORE than a dozen of the regulars, and this peer group (we're all bozos on this bus) LOL is a loosely-knit community of professionals that put a premium on enhancing their skills by contributing here...and, of course, asking questions, too.
I said when I first came here, and I say again,
THESE GUYS ARE GOOD!

Now: the capacitor matter is attracting worldwide attention as manufacturers squabble/sue/countersue/blame each other as a large number of computer components got onto the market with faulty this or thats on them. Unfortunately, the ppl who discover the error for them, the end users, are the last to benefit from the news...and may never get true resolution. BUT, we can remember who did it to us, and never buy their stuff again.
Sorta' like Mark Twain's cat sitting on a hot stove lid...who "never sat on a cold one, either."
 
The motherboard grounding out is often a culprit when a computer will not start. Motherboards also have temperature settings in the BIOS that can cause problems. Another culprit is the fans that plug into the motherboard not working. The motherboard may be stalling if a fan does not turn fast enough. Some motherboards are complex and can adjust the speed of the fans on the motherboard as opposed to running them at a constant speed all the time. This in itself could cause problems. When replacing a video card, reset the video settings back to the windows default before removing the old one. If the motherboard has been damaged from heat components may be bad. Memeroy may be bad on the motherboard or on the video card. If you do not like my post feel free to point out your opinion or my errors.
 
WolverineLogan , this FAQ may help your troubleshooting:

faq602-2731
Jim

Please come back and let us know if your
problem is fixed and what fixed it!! [thumbsup2]
 
ANFPS26 - I just took a look at this thread, and you beat me to the punch! ;-)
WolverineLogan - Two things that I would especially suggest that you look at would be:
1) (if it is there) the switch on the back of the new PSU. Is it set correctly (110v vs 220v)?
2) Is your reset button (or power button) stuck in? Like suggested above, pull all front panel connectors off (first note how they should go back on if you are unfamiliar with this process) and turn on the computer by shorting out the power button pins on the motherboard. Mudskipper
___________________________________________________________________________________

Groucho said it best- "A four year-old child could understand this! Quick! Run out and find me a four year-old child: I can't make heads nor tails out of this!"
 
Ummmm, didn't say it very clearly in my post...my bad.
That's what I intended to say: take the box leads from the case off the motherboard and then jumper the power pins on the motherboard to try starting it.
Thanks, very much, mudd, for showing me the great big wart on the end of my nose! LOL
 
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