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When my new system is powered up, the case fan and power supply fans turn fine. The CPU fan twitches, but never gets going. Although I've heard that with AMDs and Gigabyte motherboards that is not necessary a problem. Hard drive is spinning. However, there is absolutely no indication that anything else is happening. The motherboard, as far as I can tell, does not have an internal speaker, but I harvested one from another machine and plugged it in and still no beeps at all. The monitor screen stays black, on both the integrated VGA and DVI.

This is a brand new build, and has never successfully booted.

My parts are:

  • AMD Athlon II X2 245 Regor 2.9GHz Socket AM3 65W Dual-Core Processor Model ADX245OCGQBOX - includes CPU cooler)
  • GIGABYTE GA-MA785GPMT-UD2H AM3 AMD 785G HDMI Micro ATX AMD Motherboard - Retail
  • G.SKILL Ripjaws Series 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10666) Desktop Memory Model F3-10666CL8D-4GBRM - Retail
  • CORSAIR CMPSU-400CX 400W ATX12V V2.2 80 PLUS Certified Compatible with Core i7 Power Supply - Retail
  • SAMSUNG Spinpoint F3 HD502HJ 500GB 7200 RPM SATA 3.0Gb/s 3.5" Internal Hard Drive -Bare Drive
  • COOLER MASTER Elite 341 RC-341C-KKN1-GP Black Steel MicroATX Mid Tower Computer Case - Retail
  • I also have a DVD burner, but it acts the same whether that is plugged in or not.
  • I'm using the on board video.

What I've tried so far:

  • I've switched power supplies, with no difference.
  • I've tried different monitors (of which all are working on other machines) with no difference.
  • I have tried putting it one memory module at a time, with no difference.
  • I have tried the absolute minimum I can think of (power supply into motherboard, power button ONLY plugged into front panel, CPU fan plugged in), with no difference.

I appreciate any ideas anyone might have. Do I need to RMA the motherboard? This is my first build, so there might be something obvious. I was very careful in assembly with static; I'm confident nothing was zapped during assembly.

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I took each part out, one-by-one. Turned out to be the CPU must not have been properly seated. Not sure how that's possible since it only goes in one-way (yes, the triangles were lined up), and the heatsink is one of those clamp-down-against-the-motherboard-types. I appreciate the help very much! – Dave Nov 6 '09 at 18:24
BTW, I'd upvote everyone for basically pointing me in the right direction, but don't have enough reputation apparently! :) – Dave Nov 6 '09 at 18:25
up vote 1 down vote accepted

Is the CPU seated correctly? The internal speaker from the other build could possibly be of no use anyway if it isn't working itself.

By a "black screen" do you mean the monitor gets no signal? Or it gets a signal but remains black? Is there a prompt?

Sounds like a DOA motherboard to me. I'd say RMA.

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Could be the board. Lack of post beeps suggests that something is fubared there: it should be beeping or showing LEDs or something. I'd suggest checking video, but that goes right back to your board, in this case. Hmmm.

This is a stupid thing, but did you check and make sure you plugged ALL the power plugs into the motherboard? I've seen people forget the second one a hundred times. The corollary to that is forgetting to put the secondary power into the fancy graphics card (which obviously isn't your problem, but it's why I think about video).

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I had this same problem, and it was something as simple as a incorrectly seated peripheral connection.

For me it was a floppy drive, but make sure it is all plugged in fine, its tedious but make sure every thing is plugged in correctly

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Pull all cards/peripherals off of the motherboard except the video card (and if it's got on board video capabilities, go with that for the first test), the basic speaker (if not built in) and the CPU fan. Re-check the power supply to motherboard connections and try to power it up. If there's a problem with a peripheral, this will tell you that the MB/CPU is OK and then you can power down and add peripherals one at a time (start with any external video card) until you figure out which one caused the problem. If none of them do, then it was a bad connection of some sort.

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As a side note I recently had this symptom start up on a previously working computer. In my case, it was caused by failures of capacitors on the motherboard. I kinda thought that the supply chains had worked the bad caps out many moons ago, but apparently not. – Michael Kohne Jun 29 '12 at 2:27

Could be a very simple item. I missed it when I started mine.

You need the adapter to change the 4pin 12v cpu plug to a 8 pin 12v cpu plug. ( the one to the left of the proccessor and behind the back connectors of the board.

Hope this helps.

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