How to diagnose faulty MoBo or CPU?

I built a new system about a year ago. Recently the power supply failed on me causing it to produce a fowl smell and completely die. It was a ocz700sxs, and apparently everyone who bought it also had the PSU die on them within a few months. They replaced the PSU with a new OCZ700SXS2, but after i hooked it up the computer doesn't boot anymore. It seems as though everything else is fine except the CPU and possibly the MoBo. The case fans spin, LEDs light up, and GPU fan spins when i press the power button, but it doesnt go through POST, and when i try to power off the system by holding the power button down for a few seconds, it doesn't respond and it seems like it has froze forcing me to flip the switch on the PSU.
So far I've concluded that it is either the CPU or MoBo because the CPU fan doesn't spin (yes i've connected the fan cable for the CPU up and connceted the 4-pin cpu wires). I've also tried removing 1 stick of RAM, and switching the location of the RAM too but it didnt do anything. ALso i have reseated/reconnected all the compontents such as GPU, HDD, CD ROM but it didnt do anything.
So I'm asking how do I determine if its the CPU or the MoBo that's at fault? I'm afraid the PSU might have destroyed the CPU/MoBo along with it when the PSU completely failed.
Specs: BIOSTAR TFORCE TA790GX 128M AM3/AM2+/AM2 AMD 790GX HDMI ATX AMD Motherboard
AMD Phenom 9950 black edition 2.6GHz AM2+ socket
Gskill 2GBx2 240 pin 800mhz RAM

Lemme know if you need more info. Thanks!
6 answers Last reply Best Answer
More about diagnose faulty mobo
  1. First, I would pull the GPU and "hear" if it starts-up. Tell tail signs of a bad CPU is that the MOBO does nothing {CPU fan won't spin}; however what Beep tones do you hear if any?

    If you get NO BEEPS - more than likely a bad MOBO, but a bad PSU can destroy anything it's attached to {MOBO, CPU, GPU, etc}.
  2. I pulled the GPU, same thing. The CPU fan doesn't spin, and no beeps. Only two red LEDs on the motherboard kept lit, and i still couldn't turn off the computer by holding down the power button.

    Another thing that might be worth noting was that when i pulled the pci power connectors to the GPU it made a high pitched screeching noise. I dont know if it was the speaker on the case or was it a internal speaker from the GPU.

    Since no beeps were heard when i pulled the GPU, and i also pulled the CPU fan pins first, then the CPU Power. I'm assuming that the MoBo is fried?

    thanks for the help.
  3. Best answer
    More than likely the MOBO, but the only 100% is to try a different CPU or send MOBO to BIOSTAR to test. The lack of beeps sways me toward MOBO, but I've seen the CPU behave similarly with the exception {CPU Fan}; no CPU fan again another bad MOBO sign.

    Number of Beeps Description
    1 No media present. (Insert diskette in floppy drive A:)
    2 “AMIBOOT.ROM” file not found in root directory of diskette in A:
    3 Insert next diskette if multiple diskettes are used for recovery
    4 Flash Programming successful
    5 File read error
    7 No Flash EPROM detected
    10 Flash Erase error
    11 Flash Program error
    12 “AMIBOOT.ROM” file size error
    13 BIOS ROM image mismatch (file layout does not match image present in flash device)

    Best I can diagnose.
  4. Best answer selected by blkdragon201.
  5. Thanks you've been real helpful. I'm assuming its the MoBo and im gonna ship the MoBo back to biostar to have them hopefully replace it.
  6. 90%+ MOBO.

    Good Luck - Sorry it happened. :(
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