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I don't know what else to do. This is my second processor in box that hasn't worked. The first was RMA'd back to AMD and was confirmed bad by AMD.

Processor: AMD Phenom II X2 HDZ550WFGIBOX

Motherboard: Gigabyte MA790X-UD4P

Video Card: ATI Sapphire Radeon HD4870

Memory: Crucial Ballistics 4 x 1Gb of DDR 800Mhz.

Power Supply: 850W

Troubleshooting: Replaced motherboard and verified that video card, memory, and DVD-ROM and power supply all work. Replaced Processor with replacement from AMD after first processor was verified as bad. Computer posted once and asked for a disk. Once disk was inserted, computer powered off. Computer will not post after that once. Fans work. Lights work.

If you have any ideas, I would love to hear them!

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The only time I've seen a system behave as you are describing was when the processor heatsink was not installed. The system would THERMTRIP and shut off. After it cools down, it should work again until it THERMTRIP's. Eventually, it could damage the motherboard/processor, but I wouldn't expect that after just one failure.

The odds of two consecutive processors being delivered bad are very small, as well. I would first suspect something is wrong with the assembly.

  1. Check motherboard configuration. Make sure all the shunts and switches are correct.
  2. Strip down the system to the bare essentials:
    • 1 stick of memory
    • processor & heatsink
    • power supply video card
  3. Make sure all the power plugs are in, including on the video card.
  4. Pay special attention to the processor: Are any pins bent? If a pin is bent, you can usually bend it back with tweezers, but it can't handle more than a couple of bends.
  5. See if you can get the system to power up in a base configuration and add parts back until it fails. That will help narrow down what is causing the problem.

My next step would to be to check all the power rails on the motherboard with a meter. I would also work back from the BIOS to make sure the busses are running with an oscilloscope (for example, the LPC bus LFRAME_L toggles when the processor is fetching code from the BIOS ROM).

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+1 well put. don't forget to double- and triple-check that the heatsink is installed properly. – quack quixote Oct 9 '09 at 12:47

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