More of a general call for hardware debug help

[m1abrams]

So I was watching a Bluray movie when about half-way through the movie the whole pc locks. So I hit the reset button it reboots and I try playing the movie back from where it stopped. It locked in the exact same location. So I try to reboot again this time when the display goes away it NEVER comes back. so I try hitting reset again, nothing. So I try powering the machine down by pressing and holding the power button. NOTHING, machine still powered it wont shutoff. So I pull the cord.

Plug the cord back in and the power kicks right on without pressing the power button, however still no display output.

Have not had any issues with this machine since I built it a couple of months ago.

It is a Gigabyte ga-ma78gm-s2h (780G board) with a Phenom 9500. The temp. readings just before the second crash on the CPU where at 50C which is been the normal temp for this machine.

Now the really bad part, when I pulled the cover I notice the distinct smell of burning electrical (EE here burned up a few things in my time). I could not identify anything on the board that appeared to have lost its magic smoke. The northbridge chip was not hot to the touch, which actually surprised me because it normally is pretty warm. Note no HD activity lights appear when the machine trys to run, no beeps, nothing.

My first guess is either the motherboard went south or my power supply died. Due to the smell I am thinking it might be the power supply. This is the model power supply. SeaSonic S12 Energy Plus SS-550HT ATX12V

[Conejo]

It's odd that is did it twice while watching that bluray. I wonder if the decoder pulled more than the power supply could deliver?

The power button is a request through the motherboard but should function even without a processor. Something must be holding on.

Does the motherboard have on-board video and can you disconnect all peripherals and get into the BIOS?

[m1abrams]

Originally Posted by Conejo

It's odd that is did it twice while watching that bluray. I wonder if the decoder pulled more than the power supply could deliver?

The power button is a request through the motherboard but should function even without a processor. Something must be holding on.

Does the motherboard have on-board video and can you disconnect all peripherals and get into the BIOS?

Using the onboard video of the motherboard.

In the morning I will disconnect both internal tuners, data drive, bluray drive, and usb devices except keyboard and mouse. See what happens.

Going to bed now, however if anyone else has suggestions please post them.

[m1abrams]

Ok it is not the powersupply hooked up a different power supply same issue.

I clear the CMOS. One change, the power does not turn on when i plug the cord in, I have to push the power button first. Before just plugging in the power turned the power supply on. I think maybe I had the bios set to remember last power state. Clearing the bios set that back to always off.

I unhooked everything that is unneeded even front port usb and audio connections. No change.

I tried each of the 2 memory sticks alone and in different slots. No change

I even unplugged all memory sticks hoping to get beep from the board complaining no memory. Nothing

I think the motherboard is DEAD. Since it does not even beep at power on. Only other component it could be is the CPU.

[Conejo]

Do you have another compatible box you can swap components into to test? Otherwise, with *something* being dead, you could start swapping the most likely part (motherboard) and spend your way up.

[m1abrams]

unfortunately I do not have another motherboard that supports the phenom.

I tested the memory in another computer, it is ok.

So it is either the motherboard or CPU. My bet is on the motherboard. I setup an RMA with gigabyte on the board already. However that will take 2-3 weeks once they get my board! So I am probably looking at 4 weeks of no DVR. I explained that to the wife and she said how much to buy a new one

So I think I am going to pick up this board:
http://www.newegg.com/Product/Produc...82E16813128341

It is basically the revised version of the one I had, plus sideport memory. Should be able to just swap parts and go, no need to reinstall the OS or drivers. This board also has a larger NB heatsink that they put on the rev.1.1 of the other 780G. My board was rev1.0 and I wonder if the NB just smoked itself out.

[m1abrams]

Course if I buy a new board I will have an extra 780G motherboard when the return comes. May hold on to it for backup, or possible try and sell it.

[Conejo]

Don't forget about the thermal paste when you reseat the CPU, though if you layer it really thin like you're supposed to you should have plenty left over from the previous setup.

[m1abrams]

Originally Posted by Conejo

Don't forget about the thermal paste when you reseat the CPU, though if you layer it really thin like you're supposed to you should have plenty left over from the previous setup.

Have loads of the stuff.

[m1abrams]

Well my replacement board just came in, using the MA78GPM-DS2H instead of the MA78GM-S2H.

I just pulled the old blown motherboard out of the case, had not done that until now. I can now see what the failure was and it was with the power stage on the motherboard. Looks like at least 1 maybe 2 transistors blew, black goo leaking underneath them is always a bad sign. That would also explain the electrical burning smell. I knew the power stage on this board was weak however I was NOT using a 125W CPU. Glad I went with the MA78GPM-DS2H it has a better power stage that can handle the 125W CPUs so should have no issue with my Phenom 9500 95W chip.

Well on to installing the new board.

[m1abrams]

So far so good with the new board.

One difference I did not notice between the MA78GPM-DS2H and the MA78GM-S2H is that the newer MA78GPM-DS2H does not have DTS Connect but instead uses Dolby Digital Live. They both accomplish the same task, however DTS Connect might possible have provided better sound quality since DTS has higher bandwidth than DD. Though in the few tests I have done I really can not tell a difference.

[Conejo]

The specs use the same HD audio (Realtek ALC 889A) sound chip for both boards, but one is DTS and the other is DD. Strange.

Most of the audiophiles from the 'audio boards' don't seem to like using the onboard chips because they believe the motherboards have pretty poor pre-amp circuits, so they prefer to use the optical-out to a decoding receiver. But if you're a gamer with EAX sound then this might not work for you.

EDIT:
This is really confusing. A GIS on Realtek ALC 889A will reveal results that say the chip will do both DTS and DD to 7.1 analog, but some say the chip will encode DTS Connect while others say it will encode DolbyDigital Live for transport over the S/PDIF.
The Wiki says DTS-Connect is available with the Realtek ALC883DTS/ALC889A/ALC888DD-GR
The Wiki says DDL is available on motherboards with codecs such as Realtek's ALC882D, ALC888DD and ALC888H.

[m1abrams]

Originally Posted by Conejo

The specs use the same HD audio (Realtek ALC 889A) sound chip for both boards, but one is DTS and the other is DD. Strange.

Most of the audiophiles from the 'audio boards' don't seem to like using the onboard chips because they believe the motherboards have pretty poor pre-amp circuits, so they prefer to use the optical-out to a decoding receiver. But if you're a gamer with EAX sound then this might not work for you.

EDIT:
This is really confusing. A GIS on Realtek ALC 889A will reveal results that say the chip will do both DTS and DD to 7.1 analog, but some say the chip will encode DTS Connect while others say it will encode DolbyDigital Live for transport over the S/PDIF.
The Wiki says DTS-Connect is available with the Realtek ALC883DTS/ALC889A/ALC888DD-GR
The Wiki says DDL is available on motherboards with codecs such as Realtek's ALC882D, ALC888DD and ALC888H.

Well DTS Connect and DD Live are both used for digital out, not analog. I suspect that the only difference between the 2 boards on this respect is the drivers. Interesting thing I had happen was because I did not reinstall windows when I swapped boards I had the Audio drivers for the other board installed. With the new board the driver worked but neither DD Live or DTS connect options were available. BUT I could set the output sample rate to rates from 44.1khz to 192khz and confirmed it used this rate with my reciever. After installing the proper driver DD Live options showed but could no longer adjust the sample rate and it was fixed at 48khz.