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I need some help

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by teraside

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Good day. I have got a pc with a Epox Ep 3VCM+ motherboard and 128mb 133 SDRam. The problem is the pc does not start. When I press the button to start up the computer, the power comes on, but there is no power on the monitor or keyboard. I don't know what to check. This is a recent fault, since the pc worked fine for months. Please help if you can. I am not sure what processor is installed, since the motherboard supports both Cyrix and Pentium III.
Thanks alot. Jako Alberts

13 replies

by breydel

More than likely a hardware fault.

When you say the power comes on, how do you determine this - do lights come on (which ones?).
Do you notice activity on the hard drive as if it is booting ?
Do all the vents run ? (both PSU and CPU ?)
Does the screen take its power from the PC PSU ?

Much more info needed before I can make a diagnosis I'm afraid...

by 3xp3rt

You must verify if the processor fun is working.
If the fun not working of cause the dust, or other malfunction you must replace it.

by hal 9000

Start by pulling the cover and cleaning it out. The apply power and see what fans if any are running. If there is nothing working at all make sure that everything is plugged in correctly and try again.

Are you hearing any beeps from the computer? If you are list the beep number and type eg 3 short beeps followed by a single long beep. The Beep codes are unique for each M'Board but they do tell you what if anything is actually going on with the M'Board, CPU, RAM combination and you can do some basic fault finding from just listening to the beeps.

If there is no response at all try replacing the Power Supply as these do go bad and cut down the output current so that things will not work particularly it it's been overtaxed in the power demand department.

As Epox no longer lists that M'Board on its Web Site There isn't a lot more I can suggest. The obvious thing is to clean out any crud & dust that has been sucked into the case and re-seat the parts but for the time being leave the CPU alone. If the Heat-sink has come off the CPU that will be dead but if it's still in place just pulling out any plug in cards and RAM may get things working again just remember to power down and remove the power cord before removing anything and grab the case on a metal part before you stick your fingers inside so you do not discharge a static jolt into the internals of the case.

Col

by hal 9000

OK there lights on the front of the case should come on including the CD drives if you have a constant power supply. As for no Beeps check to see if there is a speaker fitted to the M'Board this should be somewhere inside the case and has a 2 wire 4 pin connector something like a sound lead but with only the two end connectors used. If you can Look at the M'Board under Light and magnification you should be able to read the front panel connectors and see where the speaker connects. If it's there and you are not getting any noise swap out the PS and I think that will cure your problem. Of course if the unit has been running with a low 5 V rail you may have lost the MBR's on the HDD's.

Don't settle for anything under 350 W and even then only if you are looking at something like a Smart Power Antec PS if it is an unbranded one go for a much higher power rating as this will be a peek rating and not a continuous rating which the Antec's are. Zalamn also make a good fan less unit but they are more expensive and with anything you get what you pay for. My son was using one of my computers during a thunder storm and a tree fell across the power lines allowing the High Tension to come into contact with the mains side of things so he had 33 KV running though the mains and it blew everything including the computer PS which has about 3 feet of flame shoot out the back and set fire to a curtain. When I learnt what had happened I expected the entire computer to be junk and quoted accordingly which the power authority accepted but when I replaced the Antec PS everything worked perfectly and has done now for 2.5 years. While I wouldn't recommend these PS to guard against things like that it's nice to know that you have that level of safety built in.

by hal 9000

One unbranded PS that I had to do an Insurance quote on in a 3 day old server had allowed mains power into the case destroying everything and then the mains power went out over the network cables destroying the entire network.

The company involved saved about $25.00 AU on a cheap Power Supply and it ended up costing their insurance company several hundred K in damages and then there was lost production to be taken into account.

Personally I would prefer to spend that it extra and save the hardware down the line rather than save a few $ now and have the entire lot of hardware destroyed latter.

Col

by hal 9000

You could always try changing the M'Board battery when they go flat the computers do some really screwy things and that just could be your current problem.

Col

by hal 9000

From what you have posted in the above I am taking it that the PS is turning on for a short period of time and then shutting down right?

If this is the case you have a problem in the M'Board, CPU, RAM side of things as with an ATX PS they start and then receive a signal from the M'Board to stay on if they do not receive this signal they shut down and effectively turn off which is my understanding of what is happening here, Right?

If that is the case then you'll need to have a very close look at the M'Board for bad solder joints or what is far more likely in an older unit bad connections between the M'Board RAM and any Daughter Cards, generally just be removing these items and re-seating them cures any bad connections but if it doesn't than you'll have to pull the M'Board and start inspecting it very closely. As Dalton has already mentioned check the Electronic Capacitors around th CPU for signs of bulging on their tops {These look like tin cans standing on their ends} and if they are any signs of bulging then forget about the M'Board put the HDD into another computer as a Slave and save whatever data you have not already saved off it. But if the Electrolytic are OK then you need to look very carefully at the M'Board and you'll need to check both sides for any signs of something that shouldn't be there any signs of corrosion or things like that mean that the M'Board s scrap Fibreglass but if there are no obvious problems you need to look at every old joint and make sure that they are all bright and not at all grainy. If you find a lot of Dull Grainy looking Solder joints you can always hit them with an Electronics Soldering Iron that is earthed at the tip but with any Surface Mount parts you can not touch these as they can not tolerate the heat.

Col

by teraside

It's an old computer that worked before. There are no stickers on the PSU, but I'd say it looks like a 300 Watt. All the fans turn on, can't see that the motherboard lights up, not sure where to look. There's not even one post beep, but the hard drives(2 drives installed) both power up, and it sounds like there's some activity on them, Only for a few secs though.
An LG cd-rom and HP 9100 Cd-writer. If you need more information let me know.

by am_sameni

Hi
Check your CPU and VGA card.then check your bezzer(speaker) of your motherboard and then say is it beeping?

by willcomp

Time for a capacitor (cap) inspection. Your motherboard may have been manufactured during the "bad cap" era.

Check caps for bulging and signs of leakage. Tops should be flat with no leakage. Leakage usually results in brown gunk on top of cap.

Caps are small metal cans. Ones most prone to failure are in voltage regulation circuit are usually located around CPU socket.

If caps have failed, so has motherboard.

Dalton

by teraside

The processor fan does come on, I've tried to clear the cmos. When the pc powers on, I see the green light on the case, the built in pc speaker is connected correctly, still no post beeps, i'll try to replace the power supply in the future. I don't want to spend anything on this pc, since it's passed it's sell by date.
Thanks for all the advise and replies guys. To the person that said I should try Linux: I cannot even access the bios, let alone try operating systems.

by otl

First check the ouput voltages on the PS, if they are way out of specs or no voltage it is a power problem.

Have seen this symptom with a controller card on the HD/CD streaming across the buss. Try unplugging all peripheral drives and leave the floppy plugged in, this should give you a no system indication on the monitor, if not could be your video card is the problem. Add them one at a time till it stops working, you will then have the bad one identified.

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