Is my motherboard fried? Help please!

knellie22

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May 6, 2010
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Warning: probably a pretty long, detailed post, though I've tried to make it a bit shorter and to the point so it's not like a big long essay!

Over the past week or so, I've received all the parts to my new computer & have began putting it together, though I'm having some issues and I'm at a loss for what to do.

Here's what's in my computer:
MSI 870A-G54 mobo
AMD Phenom II x4 955 CPU
Samsung 1 TB sata3 HDD
Lite-on DVD burner
Rosewill Destroyer case
Antec Earthwatts 750W PSU
HiS HD 5850 video card
G.Skill 4GB DDR3 RAM
Windows 7 Home Premium upgrade version

The first time I put my computer together and started it up, it worked like a charm - single beep, POST'd just fine. I was so happy! I went into the BIOS just to look around and didn't change anything, then shut it off for the night.

The next time I went to work on it, I started it up and it worked just fine, so I started installing Windows 7. I installed it just fine the first time (it's the upgrade version so I have to do the double install "trick"), and then I began the 2nd installation. An option came up that let me choose whether to download all the latest updates and stuff, or not, and I figured I might as well do it now, so I plugged in my ethernet cord, and my computer just shut off.

Quick question: is it not ok to plug ethernet cords in/out when the computer is on? I've done it probably a hundred times before on other computers and have never had a problem.

I was a bit worried that it shut off (why would it do that?), but I turned it on again. It turned on for like 5 seconds, then shut off. I don't remember if it beeped or not. I never played with anything in the BIOS - all I did was change the system time and look around at the settings and that it detected everything (it did).

After it shut off after ~5 seconds, I tried again, and it shut off after ~5 seconds again. Every try since then, it won't even turn on.

I've followed the very detailed & handy no boot / no video guide from here, and tried every single suggestion, but I've had no luck. I got down to JSC's suggestions about breadboarding, and I've done that. I took out everything from my case and have only the motherboard, CPU, heatsink & fan, and the PSU hooked up, and when I use a screwdriver to turn the mobo on via the two power switch pins, nothing happens. When I use the paperclip to start the mobo up via the a green & black wire in the 24-pin connector, it starts, although I get no beeps. I then am able to shut it off by holding a flathead screwdriver on the 2 power switch pins for 5 seconds. I don't get why I can shut it off, but can't start it up with those 2 power switch pins.

I also tested out my new PSU in my old computer, because I don't think I have a strong enough PSU to test out with my new motherboard - all I have is an old 250W one. My new PSU worked just fine in my old computer.

I'm down to thinking something is seriously wrong with my motherboard, or perhaps my PSU. Is there anything I'm missing, or am I basically left to talk to Newegg/MSI about my motherboard? What do you think?

Thanks so much for any advice/help you can give and thanks for reading it all - I know it's a lot but I wanted to make sure to be very detailed.
 

knellie22

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May 6, 2010
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*bump*

I bought a multimeter today - gonna test out the power supply, otherwise unless I get some new ideas, I'll try again tomorrow to see if it POSTs, otherwise I guess I'll have to go talk to Newegg/MSI and see what happens from there.

After my first attempt at talking to MSI (regarding a question I had about my mobo & manual), I'm not sure I want to deal with them again, as they posted a response to my question but it didn't answer my question at all, it basically just said, "here's what's in the manual." Seems like they didn't even read my entire question.
 

knellie22

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May 6, 2010
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Yeah. I'm almost certain it's the motherboard now.

I tested out the voltages on the PSU and everything was working as it was supposed to as far as I could tell. Yellow wires were at 12 volts, red at 5, orange at 3.3, blue at -12, and the purple at 5.

The only thing I wasn't sure about was the gray wire in the 24-pin connector. JSC wrote: "The gray wire is really important. It should go from 0 to +5 volts when you turn the PSU on with the case switch. CPU needs this signal to boot."

When I tested the gray wire, it was running at 3.7 volts. Is that bad, or normal?

Ok, nevermind, pretty sure he just meant that it should be somewhere between 0 and 5, not at 5. I tested my old 250W psu that works fine and it's at around 3.84 for the gray.