It is not impossible, but to find the fault, remove the faulty component, obtain a replacement, fit it and re-test would almost certainly be more expensive than replacing the board (unless you have the ability and time available to do it yourself).

In addition to JohnDG comments, if it is a multi-layer board with a broken circuit buried 4 layers down, you can't repair that.

Failure of an inner trace is extremely rare.

Most likely it is a surface mount component, but as already stated, you need to find the faulty component, then remove and replace it (assuming you can even get the part).

Reworking high density surface mount components requires sophisticated equipment.

Been there, done that, some time ago. Whole nine yards. Bed of nails testers through rework stations, assembly and shipping.

It's expensive to repair any failure on a modern multilayer PCB.

As you say, possible, but time consuming and expensive.

It is however done frequently during prototyping and development of complex circuit boards to prove bug fixes and modifications before committing to a board roll.

PC motherboards are produced in large quantities very cheaply in China, thus theyare cheaper to replace than repair.....

It is not multi layered. It is single layered. I am Mechanical Engineer so not familiar with tracking PCB circuits with multi meter. I had to call hardware engineer for the job. He told me that life of MB is only 3 years after that it dies its natural death. Very short life even of Intel original MBs.

I think the Timex-Sinclair was at least a two-layer PCB!

YOu may want to consult another technician.

Still, if the fault is not due to memory or an external peripheral, then just buy another board.

Life of a motherboard only 3 years??? Funny- I have a couple of computers more than 10 years old, still running...

I did have a motherboard failure on a newer computer a couple of years ago- I think it may have bee something like 7 years old (hard to say for sure- I bought it used- guessing based on the generation of the hardware, and what I knew of the purchasing habits of the original owner). The failure was the result of a lightning strike- not a direct hit, mind you, but close enough that the electromagnetic radiation was enough to fry a single component- quite obvious what component had died. But had it taken other components with it? Hard to say. Better to replace the motherboard.

And motherboards are not all that expensive- cheaper than a new computer...

both of my chartbook 386-sx-s failed NOT but theyr power adapters did - so i trhew them away my 286 didn't supported enough HDD (didn't fail but i threw it away coz - i had number of newer equippement) - i still have one 386AT ? from 1991 ? operational - (with rewelded (new) MB-accu.bat 3.7V) ...

i gess it's (the 3y) manufacturers warranty for quality MB-s - then you rely on your own

A modern PC mainboard, if less than 1 meter x 1 meter in size will NEVER EVER be single layer.

In fact, I have not seen a double layer mainboard in years. Not that I take such an interest anymore.....

They are invariably more layers than two I am really sure......

Simply not worth the time or energy to repair.

You should be looking for a more fundamental reason to do with maybe mains supply, earthing, bad external cabling etc etc etc to find out why the boards are going wrong.

Try a new mainboard supplier......

Suresh, if it was a two layer board, I'll eat my hat. (I don't wear hats.) AT A MINIMUM it is four layers with an embedded power and ground plane internally. I'd wager money on that. trust me, I used to photoplot PCB masks for Compaq in years gone by. most motherboards have multiple signal layers internally as well. look for doughnuts that either don't connect to anything on either side, or only on one side. that is going to be a via to an interior plane.

It is not multi layered. It is single layered.
I think you do not understand the terms. The board appears to be a single layer of reinforced plastic. But there are multiple layers of conducting traces within the board. You would need to go back in time several decades to find a single layer mother board.

Make sure it is recycled and not just dumped.

AH, is correct, but the failure is usually a plated through via hole that has separated from an interior via. usually due to thermal or mechanical stress, but occasionally due to corrosion.

I had similar experiences as Lyn, it's very difficult to repair these boards. I don't know of any main boards that are not multi-layer, chip pin density and clock frequencies are such as to make any other form non viable. I have had some success however replacing the caps with a rework station, about 50%. I believe the main reason for failure (including caps) is environmental - so it's worth spending a little more on cooling, airflow, dust filtering etc, for special and critical systems.

suggest use another manu board; you're into a bad batch maybe

if you can get schematics, you can troubleshoot to component, but still not guaranteed part is available or you have the million dollar equipment required to replace some parts. check regulators and esr all caps. only chance for repairing. really, if you have already replaced 3, maybe its time to consider different manufacture's board.

Have done heaps of component level repairs on main pcbs.

Usually just leaking capacitors but occasionally you can get distortion of the actuaul PCB ( usually caused from overheating due to leaky caps) and unfortunately there isnt too much can be done.

A distorted or warped PCB you will find affects the pressure mounted components and also ram slots etc , and can in extreme cases break multi layer pcb connections.

As others have mentioned...just replace the MB. An average technician will charge about $100-$130 per hour or part thereof. So even a 2.5 hour job will cost you over $300. Hardly worth it.

I had a go myself (being an electronics engineer) and I can certainly tell you the fault is the electrolytic caps. Most will have a 10,000 hr life, some better ones 30,000 hrs. Mind you, that is when operating at 25degC. For every 10degC above that, there is a derating curve which shows how the life of these will diminish quicker (usually halved life span for every 10degC increase - check the data sheets). Multiply that by the number of hours that the PC is on and you quickly see how 3-5yr MB life occurs. If you look closely at the MB you will notice that the electrolytic caps are all around the heatsink (design conspiracy?). When the electrolytics die, they usually short circuit i.e the supply voltages will be shorted to ground (try this yourself...get a multimeter or even a continuity tester and put it across a few electrolytic caps and check to see if I'm correct)...This short will usually kill a few ICs along the way (yes I tried removing the caps and there was still a short indicating this - so I gave up)

Best of luck with which way you go though

and higher quality boards use dry epoxy dipped tantalum caps which do not dry out, whereas cheap boards use electrolytics with have a wet electrolyte which makes them VERY temp sensitive. you get what you pay for, if you are lucky.

The caps when they go produce a very small fire on the mobo. The puffed up ends of caps are a telltale warning sign of and impending fire. The caps can be replaced and with use of a suitable glue from Masterbond rather than more fire.

Stupidity is doing the same thing twice and expecting a different result.

New laptops are $329 around where I live today.

The trouble with "engineers" these days is they are not technicians they are read the fault finder and then change the pcb that the fault finder tells him is the one thats at fault, most wiring diagrams don't show the pcb in any detail just the plug ins and lead colouring.

Bazzer

Only limited repars is possible and those are the power side.

And some people had been re-writing BIOS.

Now some gentleman has already pointed out why?. Now multilayerd PCBs need more sophisticated Tools and Equipment including SW from manufacturers.

Thanks to all for your comments. My point of view is that when every electronic gadget to day is being made smaller and smaller but what about maintenance, which is rather very difficult, more over in PCBs for computers, TVs. washing machines etc. Why poor customer is forced to pay for complete PCB where as only few components are dead.Remaining components are simply scraped. It is just wastage, cost of which is borne by innocent customers like me.

When I was in the computer business, it was the "innocent customers" that caused about 80% of the failures one way or another......blocked cooling, overheated server rooms, you name it they did it.

I once went onsite to find all the operating staff in shorts and no t-shirts because the AC was broken, temperatures in the high 40°C...but all electronics were switched on.....

It took months to re-stabilise that site.....

Look to the stuff around your PC. I wrote already about that.

Before the days of printed circuit boards, components were wired from point to point with insulated wire. I built a tube-type stereo amplifier this way. We could still make things that way so that people could easily make repairs. Unfortunately, your smart phone would be the size of tractor trailer truck (big lorry), would cost more than a tractor and trailer combined, and still, many features could not work.

In the good old days, an RS232 port adapter for a TI 99 computer weighed about a kilo, cost about $250 and sat beside the computer console. Now, an RS 232 port chip costs less than $1, and is much smaller than the cable connector itself. An old TI 99 RS232 port adapter could be repaired for perhaps $100, depending upon the issue. A new RS 232 adapter chip could be replaced for $1. Which makes more sense?

Miniaturization (and the huge cost savings that go along) has allowed computers to be in every house in the developed world and in many homes in the developing world. Without miniaturization, much of what we take for granted would not work, and all of it would cost far more, by huge multiples.

Computers are incredibly easy and inexpensive to repair now: swap out a power supply or a motherboard or a graphics card, etc., etc. Complaining about non-repairable motherboards (which are now available as single chips) is like complaining about not being able to repair a CPU chip: the miniaturization that allows these things to work precludes their being repairable.

further, without multi-plane pc boards, modern CPU clock frequencies would not be possible, the RFI/EMI generated by the CPU clock radiating into other parts of the system would completely scramble the system's operation. that is one of the functions of the buried planes, another is to prevent ground loops from forming.

I repair PCBs every day including PC mother boards. The majority of the faults can be separated into two types, those due to external causes, (shorts/overvoltage, etc) and failure of on-board components - mainly batteries or electrolytic capacitors. The capacitors usually show signs of physical damage - bowed ends, leaking electrolyte. They often cause damage to other components, (Mosfets) on the circuit they are supposed to smooth by drawing excess current as they break down. Dry solder joints are another problem on PCBs, especially at connecters and switches. Use a good illuminated magnifier to examine the whole board before touching a soldering iron.

Use a multimeter to locate a shorted +5V, +12V power track, but these tracks will usually be burried in the PCB layers so you can't isolate track sections to find which component is causing the short and this is when the repair usually gets B.E.R.

If you absolutely must repair the PCB most on-board components can be replaced if you have the right tools, a lot of patience and the new components - these can be expensive or unobtainable. First tip is to chop out as much of the component as possible to reduce the amount of heat needed to remove the pins. Replace 85C capacitors with 105C to better withstand overheating.

My advice would be to use the opportunity to buy the latest replacement mother board and save yourself a lot of trouble, but please remember to check all the other equipment connect to the mother board before switching on or you could end up with a second U/S board!!!

Hi. I am an electronics engineer & regularly build high end desktop computers and servers. Let me help you w/ this issue. Need info: 1. manufacturer of MOBO (motherboard), 2. model, 3. have you R & R'd (removed & replaced) the same board each time? [same mobo model board]? 4. Symptoms upon failure- same each time or different and list them. 5. need info on this system: 5.1.: microprocessor being used; 5.2: amount of RAM (system memory); 5.3: how many peripherals? hard drives? floppy drives? CD-DVD drives?; 5.4: how many watts is power supply and name of power supply manufacturer; 5.5:

With this info I can get an electronic picture of what you are dealing with and can diagnose more intelligently. Info offered by others is good info and is substantially correct, They are well informed and knowledgeable engineers; but I strongly suspect problem is the same each time and has caused same failure each time. Dealing w/ same failure in same way each time has clearly NOT addressed the correct issue and failures therefore continue.

You can also email me at: paul_melnikov@yahoo.com or fone me: 314.363.0224; [time zone = GMT -5 (eastern time US)]. I will be pleased to help you solve this.

Dr. Paul Melnikov

I am replying below questions asked by you:-

1. MB is Intel Pentium 4. Intel Desk Top Board 01066C

2.Pentium 4.

3.No

4.Late starting of PC around 1 hour.

5.1 Intel Pentium 4.

5.2 4 GB

5.3 One HD, one CD.

5.4 Not known to me.

I am located in India. I hope above information will be sufficient to help me to avoid for future failures.

Suresh: Because of the obsolete status of pentium 4 processors, and my complete inability to find any info for an Intel motherboard delineated as 01066C, the info I can provide will have to be less than conclusive. However there are several issues I can easily comment upon to your benefit. 1. I assume you were building these systems from motherboard up, w/ less than a lot of experience building electronics. A 1 hour start up for a PC is something I've never encountered. I can tell you the exact order in which software should be loaded onto a bootable hard drive for running a PC and I'm almost 100% positive that order was not followed. 2. The size and wattage of the power supplies you used was not known to you, you said, but there is a likelihood that repeated system failures indicates, at least in part, that power supplies used may have been completely inadequate. 3. Did you ever call for assistance from Intel, to their tech support line? I failed to ask you this but the answer is important. 4. There are a number of build quality issues and wiring issues and cabling issues and grounding issues that a less than experienced system builder would be unlikely to know about, but of which ignorance could most surely lead to repeated system failures. Attending to these is far more likely to yield good results for you, than anything that can ever conceivably be done to repair any component failure of any motherboard.

Since info of several types is unknown to you, here's my concrete suggestion: If you wish to build more systems in the future, let me walk you through the building process or get a local knowledgeable individual to do so. Next, let me, or some other person, walk you through the process of installing a minimal CD program to initially read CD's for loading drivers, then loading the board level driver-operating s'ware, then configuring the BIOS s'ware, then loading operating system s'ware,, then loading peripherals like hard drives and DVD-CD drives, then loading applications s'ware. That's the order in which it must be done. Any other order will yield poor results or a very poorly operating, if at all, computer. I gave you my email and fone number. I will be happy to help you in the future. Truthfully, building these is lotsa fun (for people like me, any way), and the resultant systems function almost perfectly for the purpose for which they were built. But if not done w/ attention to several critical procedures, will result in failure after failure after failure. This is the best I can offer you, but again, I'll be happy to help you build in the future. Dr. Paul Melnikov

Hi Pmelnikov,

Many thanks for your suggestions/comments. This PC with new mother board is now functioning O.k. Here in India many PCs are just assembled units. I am not a computer wizard so naturally I did not know protocol of loading software etc.

Any how fed up with Desk Top unit I have recently got new Del Lap top from my friend from U.S. I hope I will not face new problems related to Lap tops. I wanted to dispose off 2 Nos. MBs which are supposed to be defective. Scrap dealer has offered me $1.00 for each. What a waste of money as many of components can be still salvaged.

The failure here was that no one offered you any help. That's the real failure.

If not constructed w/ attention to those things I mentioned as being critically important- failure was assured. If s'ware was not loaded properly in terms of order- s'ware exists as layers- it will never ever function- certainly not properly.

One email from a colleague, 1 hour of instructive conversation w/ someone like myself explaining the things that must be given attention and care- that's all that would have been needed to almost guarantee fully functional machines. Why is it that everyone only thinks in terms of money, and others seemingly delight when others fail. Human society is going downhill, not up.

No one seems to care to help someone else w/ a difficult, demanding electronics or engineering task. The hand is outstretched, not to offer help but only to demand money. Why is this????

You have my email and fone. Contact me if I can ever help. I have PhD's in elec engineering and in physical organic chemistry. After 6 years working for the UN in Iraq, I returned to US to an economically ruined country and global economy in tatters. I've been unemployed since then. No one thinks in terms of anything but money and that's more than just sad. Let me know if I can help.

most of that stuff either takes a lot of labor to remove without damage, or simply can't be removed without damage. so yes there are still useful parts, but extracting them usually costs more than they are worth. remember all those chips are BGA's which have hundreds of little solder ball connections under them, if even one cracks off the chip you are hosed.

My old Intel MB P4 failed recently (born 2/2003 - died sick 5/2012). For several weeks prior to failure, there was an increasingly long delay between pushing the power button and the system actually booting. This seems similar to your problem.

Quick exam of the MB revealed 2 "blown" capacitors. I replaced these with better quality capacitors (lower ESR + higher temperature = $1.50 each part, my labor). System was still dead. Pulled power supply and tested voltages under load. BAD power supply also!

Since my local electronics recyclers sell tested good used ATX power supplies for $3, I opted to buy one of these over diagnosing and repairing my power supply. Retested replacement p.s. and verified it was good. System now repaired and it operates normally.

My local recyclers were also selling a tested good version of my old MB with processor, heat sink, fan, and all cables for $20. That would have been the next best option if my simple capacitor repair failed OR I damaged the PCB during the repair.

"Some" through-hole and surface mount components can be easily replaced with low cost tools and a little knowledge/skill. Other parts, like ball-grid-array integrated circuits, require very specialized tools and extensive expertise to replace. When these parts go bad OR if there is physical damage to the PCB itself, the best action is to find a replacement MB and send the old one to your local electronics scrap recycling center.

Recyclers here used to CHARGE you a drop-off fee! Thankfully, they now accept all old electronics free of charge. They've never offered to pay for any items. I'd take anything your recycler offered for the defective parts.

Some will be puzzled why anyone would care about or spend ANY money on an old P4 system. These old computers do tend to run horribly slow, or not at all, with newer versions of Windoze. However, they run much faster and more reliably with Linux. I expect to get another 2-3 years from this particular P4 system, extending its useful life to ~12 years. IMO 9 years is very good for computer life. Anything beyond that is excellent.

I wish you better luck with your laptop .

i gess we can draw an analogy to med. surgery

many stuff can be fixed in human but it requires a methodology and training

with human ... they are mostly similar

with PCs' MBs' they are countless - you set the world wide announcement to find the guy that has the experience , (assuming he/she's interested - has time for) , TNT or DHL your stuff - to repairs and back - ...

it's theorethically possible

i gess it fits to this topic:

years ago i wanted to buy a sondcard they only manufacture in U.S. CA
where i live the common method of payment is a bank-transfer
they accepted credit cards only (my local bank officiant told "theres no way you can limit the sum for month ... ? they (cc-s) are safe in common ?")

since i'm not (yet) complete idiot - i forgot about this topic

it's amazing how developed our world was then ... gess the things haven't much changed from there ...

so i need to go in person to CA to get my stuff visa air-tickets - travel inshurance ...
this is civilized - if you didn't know

have you considered paypal? or perhaps moving to a more civilized part of the world?

The economy is based entirely on growth.If it does not grow, it dies.Growth is enhanced by limiting the lifetime of products.The emphasis now is not on quality, as it once was, but on selling more product.Quality of most everything has decreased in the last 40+ years.

I have an old round-corned GE refrigerator that is 65 years old, and still quietly and reliably does it's job.

I have a 1948 Ferguson tractor that still runs great, with all original parts.

A 1948 Allis Chalmers tractor that likewise can still "Gitter done".

The old Allis has shims on everything.When the steering box had too much slop, you adjusted the setscrew.When you ran out of setscrew length, you removed a shim and started again from the top.The same on the rod bearings.If a farmer started losing oil pressure, he removed the oil pan,took out shims from between the connecting rod caps, and put it all back together;About a 30 minute job due to the simplicity of the durable design.(The shims were tapered to compensate for out of round).

When this old tractor completely wore out, there was theoretically nothing left except shims .

Anyway, today the focus is on short term profit,quarterly return,and myopic management for the immediate future.Let the next generation worry about it.

I once worked on an old Sears(circa 1960's) tv with vacuum tubes.I had some old tubes in my tube caddy, and replaced a rectifier tube, and the picture was perfect.Color was great, no convergence adjustment required.The tv was so old it had a "moldy" fringe around edge of picture tube.

Sure I am a cynic, but I have seen too much to be naive.

I have seen tv's fail one week after warranty period.Many times.So I know they can analyze component life accurately.

Modern failures are by design to encourage growth.Get used to it.

Well looks like my options are limited.. not many places I can find that do any kind of computer repair aside from virus removal.

Think I'm just going to sell the CPU, CPU cooler and Mushkin RAM. Guess the mobo is free to anyone who wants it.

Seems I'm the one doing all the hard work and not getting paid squat, yet the idiots who sit and do nothing all day get what ever they please. Maybe I should start doing half assed jobs too!!