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Is Anyone here good enough to know how to repair a motherboard. The basic basic problem is that my 760GXK8MC motherboard wont display anything on the monitor at all. I would like to know how to diagnose the problem and if you can how to repair

Thank you sooooooo much to anyone who helps me

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Last Post by dbritanico_ph
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Ihere isn't much you can "reapir", except replace one of the components that is not working.
Figuring out which one it is is the biggest task.

Only way to do it is the process of elimination:

Unplugg all the cards, drives and RAM sticks and try turning it on. If you dont get anything (beeps, post, video feedback) that would leave 3 possibilities: CPU, motherboard and PSU.

In case you make any progress, plug one thing at the time, and ONLY one at the time.

Btw, are there any beeps? Please post their sequence (Ex. bad VGA would make 1 long 7 short beeps)

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I have already dont worked you that it is the motherboard. So I was asking how do I diagnose the problem the motherboard has (i.e is it the bios, is it that the bios isnt getting power or is it something else. If you read post "760GXK8MC" you can read the full details of what happens. But I think it is the motherboard. So I want to know how to fix a motherboard or replace bios or whatever.

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sorry I mean I have already worked out that it is the motherboard

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Trying to repair the motherboard on a component level is a daunting task. Due to miniaturization there are few components on the motherboard that you can trouble shoot. If you look on the back of a modern motherboard you will see that most all of the components a surface mounted and very few components are though hole soldered. Most of the through hole devices are actually expansion slots or sockets. Even most of your ICs are surface mounted now, and even if they weren't how would you go about testing these? About the only component that you can check are the electrolytic capacitors, and most of the failed ones can be recognized by rounded tops, and may even leak at their bases. Other than the occasional diode that's about it for components. You can look for burnt traces and arc marks, usually if there's been a shorted connection there will be a visible smoke residue on the board.

If you are sure that the motherboard is the problem...replace it.

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I cannot "see" anything wrong. I think it might be the bios can I replace this??

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Yes you can. That and CMOS battery are only things that one can replace on motherboard.
BIOS replacement is needed ONLY after a bad flash. No need to go and buy a new BIOS if the motherboard is fried. So, did you flash the BIOS before it stopped working? There is a way to recover without buying another BIOS chip. All you need is floppy drive, bootable floppy disk and BIOS file/flashing program.

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you have not told us what happened. Only that you "know" it is a motherboard problem. The only advise anyone can give to you is to go and buy another motherboard.

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Is Anyone here good enough to know how to repair a motherboard. The basic basic problem is that my 760GXK8MC motherboard wont display anything on the monitor at all. I would like to know how to diagnose the problem and if you can how to repair

Thank you sooooooo much to anyone who helps me

The original question was - Do anyone know how to repair a motherboard. Yes I do but you must really love that motherboard or it is a family heirloom. Since they are so cheap today, why repair?

I have been fixing component level problems for the last 15+ years and only recently discovered that only laptop motherboards are worth repairing. So you will need to make a decision on what to do, I don't think there is an OJT forum to tell you how to fix it, especially if it is not your field. It's not like changing a lightbulb.

aka Kegtapper

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Hi, I have the same problem with my 760GXK8MC mobo so I wondered if you solved your problem by changing you mobo or did you need to replace anything else?

Thanks.

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Lets see, to get you started in repairing that motherboard of yours, you will need an "o" scope. power supply, and a detailed schematic of that motherboard. with out these items, it is best to follow the advice of those that said to trash that one and buy another mobo. The cost of a GOOD 'O'scope will be a lot more than the mobo.IMO

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Lets see, to get you started in repairing that motherboard of yours, you will need an "o" scope. power supply, and a detailed schematic of that motherboard. with out these items, it is best to follow the advice of those that said to trash that one and buy another mobo. The cost of a GOOD 'O'scope will be a lot more than the mobo.IMO

In my opinion you don't need a scope, but a good digital meter helps. And the ability to follow traces, and read part. It's good to have them but a good tech can get by.

Plus troubleshooting could be a good lesson, especially if you find it's a fuse, bad jack or something so basic could save you 150+.

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In my opinion you don't need a scope, but a good digital meter helps. And the ability to follow traces, and read part. It's good to have them but a good tech can get by.

Plus troubleshooting could be a good lesson, especially if you find it's a fuse, bad jack or something so basic could save you 150+.

I stated this at the very first of this thread and I repeat, there are very few components on the board that can be tested with a multimeter alone. The throughhole soldered components are about it, the rest are so miniaturised or so complex that you need specialized equipment to test them, the chips set is a prime example. Another problem that you don't even begin to address are components like electrolytic capacitors that in most cases will need to be discharges and at least on leg separated from the circuit in order to be tested, and then may require an external power supply to be accurate...get real, this is not for the novice. This is about as realistic as saying that you could mow you lawn with a pair of scissors, yeah...you could do it, but who would want to?

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Not to mention that the board itself is multi-layered, so if you try to solder some component on it, you'll probably do more damage.

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I stated this at the very first of this thread and I repeat, there are very few components on the board that can be tested with a multimeter alone. The throughhole soldered components are about it, the rest are so miniaturised or so complex that you need specialized equipment to test them, the chips set is a prime example. Another problem that you don't even begin to address are components like electrolytic capacitors that in most cases will need to be discharges and at least on leg separated from the circuit in order to be tested, and then may require an external power supply to be accurate...get real, this is not for the novice. This is about as realistic as saying that you could mow you lawn with a pair of scissors, yeah...you could do it, but who would want to?

Remember it was my opinion, and I have repaired them to the component level. I forgot to add, Multiple levels of magnification, and tweezers will be needed. Most of which goes without saying.

However; I was trained by the old school method in Electronics, not just computers. Martin-Marietta, Genesco and other military contractors made sure the fabrication of multilayer PCB and the correct way to do it was taught. Many 'matchbook cover' schools are pushing out 'techs' and they really don't have the skills in fabrication and micro assemblies. Soldering alone was a 40 hour class (160 hours total). Double 00 to 24 gauge wires, PCB, bifurcated terminals and the whole shebang. SMT were a new thing at the time, and was able to get trained on that as it developed. Later microscopic fabrication with needle point soldering iron, and gold bonding on hybrid transistor substrate. So NASA/Milspec training and certs came in handy, even before A+ was considered a course.

I often get re-work from other techs, and understand the challenges, which they will often forge ahead into an area where they are not familiar. Which boils down to, if you don't know what you are doing, you should not attempt. What I won't do is discourage any Technician from fixing their own board, especially if they have a replacement handy or unable to find a skilled tech in their area. If you have nothing to lose, go for it.

I've never been afraid to give a laptop board back and say that it is too far gone, especially after spills where 4+ parts are shot. That surpasses the cost/time factor.

Remember it was my opinion, not rule of thumb.

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Just curious here...do you have any breath left after beating yourself on your back like that?

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Thanks Kegtapper. You're my kind of Tech. I'm one that "forges ahead." Thanks for not being discouraging. My motto is "anything is repairable," but as you said in your post, it's not always worth it. I'm just starting out getting into motherboard repair. I've done capacitors and jacks, but I'm trying to get into more detailed component level work. I'm trying to learn how to determine what parts are bad. I've heard that on laptops usually MOSFETs can go bad. Is that correct? Any other tips for a guy just starting out would be very helpful. Thanks again.

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Thanks Kegtapper. You're my kind of Tech. I'm one that "forges ahead." Thanks for not being discouraging. My motto is "anything is repairable," but as you said in your post, it's not always worth it. I'm just starting out getting into motherboard repair. I've done capacitors and jacks, but I'm trying to get into more detailed component level work. I'm trying to learn how to determine what parts are bad. I've heard that on laptops usually MOSFETs can go bad. Is that correct? Any other tips for a guy just starting out would be very helpful. Thanks again.

There is no "Golden Fix" when repairing at PCB level. Yes on certain products there are "Stock Faults" but only on certain systems and products.

By just saying "Oh I was told these broke the most, blew most of the time i'll replace that" is abit of a hash job. If you have proper schematics and voltages for the board when it's POWERED UP and not powered then you have a chance. Plus knowing what the voltage and resistance of the CPU and other components should be at in a normal state is half the battle.

Just dont assume anything in this game, it'll bite you in the arse later on. Full and proper staged work through is the only way to cover yourself against repeat failures. Plus knowledge of the product is advantageous, you can only do this by playing round with it and sometimes making faults worse than before :D

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techo t- I know exactly what you mean, sometimes it is not so easy to have a working model right next to you, or have the schematics. Thats where pure logic and reasoning comes in.
How I discoverd the biggest headaches with HP DV4000. The unit came in, NO POWER, NO LIGHTS. subsequent tests on the board had power in every circuit, it just wouldn't come in.

The next afternoon another came in for a different issue. I substituted the on/off panel from B to A. The unit came on. So I looked under a magnifiying glass at the panel A, and saw that oxidation on test points of the board had eaten away the traces! So I hardwired a 24ga wire from the on/off switch directly to the pad at the ribbon cable. Tacked down the wire with hot glue, and the system was returned to normal. Estimated cost, $50 labor,

otherwise it would have been
35 for keyboard
10 for shipping
100+ labor (not my charge, but what the shop charges)
and down for about a week and a half waiting.

Be very wary of Chinese designs (which most are) - seems no consideration is taken on repairs later, and if it is - it is made to be near impossible as they can. Such as extremely narrow separation between electrical potentials on DC jacks, an unskilled eye will not see a short after replacing. Now I have started taking my camera and macro lens to catalog intentional defects in designs.

Another tip! Throw No Motherboard away... you might need one small part later. Such is the case with DELL 600m/D600 RV1 and RV2 are like soldering grains of sand. When they fly off, POOF they are gone!

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i split the socket by trying to fit an agp card in it ;)

LOOOL! That one is for the grandchildren.

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techno t - Point taken, I won't assume anything or go replacing good parts just because the problem is common. I will, however, focus my first observations and tests on parts that commonly fail. For example, I will look for bad capacitors and test them. (As a side note, I have found that most of the time, you can test caps while on the board, contrary to what an earlier poster wrote. I know this because I pulled the same reading off the same capacitor before I desoldered it as I did afterwards.) When I asked if MOSFETs were a common problem in laptops, I was simply trying to verify if what I heard was true.

@all- Is there a way to test MOSFETs to determine if they are malfunctioning?

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techo t- I know exactly what you mean, sometimes it is not so easy to have a working model right next to you, or have the schematics. Thats where pure logic and reasoning comes in.
How I discoverd the biggest headaches with HP DV4000. The unit came in, NO POWER, NO LIGHTS. subsequent tests on the board had power in every circuit, it just wouldn't come in.

The next afternoon another came in for a different issue. I substituted the on/off panel from B to A. The unit came on. So I looked under a magnifiying glass at the panel A, and saw that oxidation on test points of the board had eaten away the traces! So I hardwired a 24ga wire from the on/off switch directly to the pad at the ribbon cable. Tacked down the wire with hot glue, and the system was returned to normal. Estimated cost, $50 labor,

otherwise it would have been
35 for keyboard
10 for shipping
100+ labor (not my charge, but what the shop charges)
and down for about a week and a half waiting.

Be very wary of Chinese designs (which most are) - seems no consideration is taken on repairs later, and if it is - it is made to be near impossible as they can. Such as extremely narrow separation between electrical potentials on DC jacks, an unskilled eye will not see a short after replacing. Now I have started taking my camera and macro lens to catalog intentional defects in designs.

Another tip! Throw No Motherboard away... you might need one small part later. Such is the case with DELL 600m/D600 RV1 and RV2 are like soldering grains of sand. When they fly off, POOF they are gone!

Chinese designs are a PAIN!!!!!!!1 cheap build quality and poor solder joints being made. And now with lead free coming in the poor solder quality is really affecting mainboard connections. BGA's are failing at a rate of knots and the whole thermal problems are getting worse as the lead free joints are more brittle then tin/lead soldering.

Damn cheap builds and lead free soldering really dont mix, I had a laptop in the other day, intermittant as hell. Seemed more stable once warm, struck as a poor solder joint somewhere, luckily saw that it had a few memory issues once it did boot so resoldered the lead free DIMM skts with normal tin/lead solder. Fixed it first time :D however not all fixes are as easy as that, and lead free is making things a whole hell of a lot harder:'(

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Soldering is the main price-setting factor for any piece of electronics. "Cheap" usually translates to "low quality soldering done here".

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