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Pardon my ignorance here. I finally decided to put together a computer and egads. I purchased a new motherboard, power supply, processor, video card and memory.

  • ASUS M4A79XTD EVO AM3 AMD 790X ATX AMD Motherboard
  • OCZ Fatal1ty OCZ550FTY 550W ATX12V v2.2 / EPS12V SLI Ready 80 PLUS Certified Modular Active PFC Power Supply
  • AMD Phenom II X4 965 Black Edition Deneb 3.4GHz 4 x 512KB L2 Cache 6MB L3 Cache Socket AM3 125W Quad-Core Processor
  • XFX HD-577A-ZNFC Radeon HD 5770 (Juniper XT) 1GB 128-bit GDDR5 PCI Express 2.0 x16 HDCP Ready CrossFireX Support Video Card
  • G.SKILL 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Dual Channel Kit Desktop Memory Model F3-12800CL9D-4GBNQ

I've got it all in the tower. I put in power supply, installed processor on motherboard, installed heatsink, put in ram, and I am using an older IDE hard disk.

When I start the computer, the monitor tells me "check signal cable." As far as I can tell, the processor's cooling fan is spinning, the power supply is on (obviously), and the green LED on the motherboard is on.

I originally only had the bigger output plugged into the motherboard (what I saw in a YouTube vid as well as the mobo instructions), but after doing some research, it said plug in the other ATX power supply. Which I did. And trying to power the computer results in nothing.

No beeps on startup, no post. Does anyone have any ideas? Your ideas and help is greatly appreciated.

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Is there any BIOS fitted? – Andy Apr 17 '10 at 9:22
@Andy... what? I don't think I've ever come across a motherboard with a missing bios chip. – RJFalconer Apr 17 '10 at 12:47
@BlueNovember... Haven't you? I have. It's a remote possibility I agree, but a possibility nontheless. – Andy Apr 17 '10 at 17:06
What is your M/B's revision number? Says you need a 1.01g for that CPU (if I'm reading correctly); . – therube Mar 4 '11 at 4:19
@user34479, you did turn it off before plugging in the ATX power connector right? o.O – Synetech Mar 4 '11 at 4:42

Relatively new CPUs won't work unless you plug an additional power connector into the motherboard. It's square form, about 1cm width.

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Right, use said that he plugged in the ATX connector. – Synetech Mar 4 '11 at 4:43

I had a similar problem when I rebuilt my PC, with similar parts. I thought I fried /broke something while putting it together. Even though the fans & leds had power, I finally unplugged and re-plugged all of the power connectors, and it booted right up. Apparently one of them wasn't seated correctly.

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I had a similar problem putting together a new system - it turned out that the motherboard was DOA.

I pulled the motherboard out of the case, to ensure that it was not short-circuited against the case. I even unplugged as many components as possible, but same result - no POST.

You may have a dead motherboard, unfortunately.

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the monitor tells me "check signal cable.

Monitor cable connected to the video card or onboard video (if available)?

Try clearing the CMOS.

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Actually, he said nothing about installing the video card… ;-D – Synetech Mar 4 '11 at 4:43

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