Gigabyte motherboard stops working

have a gigabyte Ga-ma78gm-us2h mobo with amd 7850 processor. suddenly stopped! Now occasionally it will run normally for a short while, but most times it will not POST....no beeps ....just power on. Tried swapping power supplies but made no difference. Any ideas what to try next?
 
Try to boot it with minimum hardware, i.e. one RAM module, use onboard display and see whether system POST normally as it should or not.

Also, clean your system using air canister to get rid of any dust etc.
 
Archean offers the probable solution... Start out with the most simple install you can... then when it is working on one hard drive, one CPU, and one memory module... add and try, keeping good notes.

Keep very good notes of what you do, and what results... as it may take you off in many directions.

Clean your thermal paste off the CPU cooler, and reapply in the thinnest possible amount.
Exchange the one memory module for another...
Suspect your power supply, cpu fan, and anything in a PCI or PCI Express slot even if unused... as anything plugged into the power on the board can be contributing to the problem.
 
Try this workaround: Before starting the PC switch off the power supply for 15 seconds or so. If the power supply has a rocker switch at the back, use that or if not, just unplug it. After switching it back on start it normally and see if it works. This is not a cure but if it works, it will let you use the PC for the time being.

If this works, the motherboard is bad. Make plans to replace it.
 
I tried the minimum hadware setup....just MOBO, 1 Memory stick and Processor....No success. Swapped out the PSU with another also made no difference. Don't even get any BEEP codes when I try to start. Tried moving the memory to other locations and tied swapping it for another stick...also no success. The question is whether it is MOBO or Processor or both? I am suspecting the MOBO< because occassionally it does boot normally....but is there a way to confirm this?
 
Damaged or defective system board. Is it still under warranty? If so, do not mess with it, as they will not honor if they can detect attempts to correct the problem.
 
Unfortunately the board is just out of warranty....I guess its time to replace it.
Thanks for the helpful suggestions.
 
hard to believe it!

Its hard to believe, but I have replaced the motherboard and I still have the same problem with the same symptoms.
REplaced the motherboard with a new board, still won;t POST....I have already tried swapping the power supply.....and tried booting in a minimal confoguration. Now the question is, whether it is a processor failure or a mempry failure. Is there any way to determine which (besides swapping, since I don';t have a replacement processor available) Anybody have some good advice?
 
Try removing the motherboard from the case and place it next to the case on a non-static, non-conducting surface. Leave the CPU, heatsink/fan and front panel connectors in place and besides that only install one stick of RAM and a graphics card (not needed if you have onboard graphics). Connect all of the power cables to the motherboard and graphics card if applicable. Connect to the monitor. For purposes of this test you don't have to connect the hard drive, optical drives, floppy drive (if you have one) or any expansion cards.

Now turn it on to see if it will post.
 
Well, you have a great start.

As always, I like mailpup'ss suggestions.

There are so many things to check... bad memory module or bad power supply being the most obvious, but grounding issues, cable issues, electrical issues connecting to the wall... bad CPU, bad CPU fan, too much CPU thermal paste rather than too little.

I would start with trading out the power supply with another, then the most simple possible connection... motherboard, CPU with thin thermal paste, one memory module, new or different CD or DVD player, and try booting to a simple Windows disk... If it works, change a component... keep on going, keep on changing, test every combination in simplicity, and once those all check out, start over with more complex setups...

You may have to do all this to track it down... But distrust the power supply it can make all the noises of one that is working, but can still be totally shot... then distrust the memory... any one module is enough to test... Keep changing those modules around.
 
Here is my latest attempt to diagnose the issue:
New motherboard (old one was the first suspect) Ga-ma785gm-us2h
borrowed known working power supply Coolermaster 500w
borrowed known working single stick of memory patriot 2 gB ddr2-800
MOBO outside the chassis on insulated base
no DVD, no hard drive
just a monitor (not even a keyboard or mouse) and using internal video.

Same symptoms......no POST Nothing. Must be the processor? (AMD7750)

Any further thoughts? Anyhting else that can be done to confirm this? (Although it seems pretty likely to me)
 
As the rest of the components have been known to be working perfectly, I would agree with your assertion that somehow your processor is fried or something like that. Hence, you may need to buy a new one for your pc.
 
It seems inescapable that the processor is the problem. As Archean said, all the rest of the components are known good so this is the only thing left.

It could still be under warranty so it might be worth checking into an RMA (return merchandise authorization) from AMD.
 
Don't give up without changing out that CoolerMaster 500W... we have seen those fail on one rail and continue to appear to be working...

You can probably borrow a power supply for a short test.

Otherwise, I think mailpup has a good guess... although it is so extremely rare to see a CPU fail unless you have had serious cooling and power issues, or a bad motherboard.
 
Have similar problem but a10 6800k apu and gigabite f2a85xm mobo tryed change cpu fist but still same now thinking about giving up on system and starting from new mobos ram and psu and test cpu because on old one find burned line on cooper surface
 
Have similar problem but a10 6800k apu and gigabite f2a85xm mobo tryed change cpu fist but still same now thinking about giving up on system and starting from new mobos ram and psu and test cpu because on old one find burned line on cooper surface

This is an old thread. I suggest starting a new one and give us your system specs including your power supply. In addition there are several offerings of the Gigabyte F2A86XM. Please give us your exact board model number.
 
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