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Sys Boots from breadboard, but not from case.

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May 9, 2012 1:37:46 AM

i52500K
asrock Z68 Extreme3 Gen3
Gigabyte 7950
ocz zt 750w
8gb 1600 g.skill

Need a lil' help. So, I bread-boarded the system last night (with the gfx card in) and it booted right up--displayed the proper amount of ram, processor speed, and what not, however I think I may have a defective post speaker, as it doesn't beep. Today, I installed everything in the case (HAF 922), and nothing, not even a sound. No lights, no fans turning, nothing came on. It's like it's getting no power.

So, I took out the MOBO, re-bread-boarded it (everything worked again, like a charm??) checked for debris/wires behind the board, checked the offsets too--couldn't see any issues, so I reseated/refastened everything, double checked for solid connections--all good. Hit power--nothing. Again, no lights, no fans spinning, nothing. The only thing I can see that may be shorting it is the back plate of my 212 evo, it's actually touching the metal of the case. It looks like the cut out is too high at the bottom of the notch, as it comes up the back plate about a 1/4" and is actually making contact.

Any help would be mucho aprreciated. I will be happy to provide more info if necessary!
May 9, 2012 2:00:45 AM

If you think it's the evo, have you tried the stock cooler to see if that's the problem? Although, it isn't the actual metal heatsink that's powered, it's the fan itself, so no electricity would be running through the heatsink.

Did you try powering it on straight from the mobo power button?

Only other thing I can think of is the motherboard plate of the case touching contacts on the mobo itself.
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May 9, 2012 2:28:45 AM

If it's working outside of the case, but not in, then most likely it has to do with something touching the case. I'm assuming all case leads are connected properly to the mobo as well.
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a b B Homebuilt system
May 9, 2012 3:33:09 AM

Are you SURE you have standoffs mounted ONLY where there are mobo screw holes. and nowhere else?

Here's an odd one I stumbled across. I noticed once when I mounted the mobo into the case that, on the back cover plate for all the ports of the mobo, one springy finger of one opening had slipped inside the connector next to it. It was supposed to be outside, making contact with the outer grounded shell of the connector. If I had not seen and fixed it, it could have shorted out things inside the connector.
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a c 84 B Homebuilt system
May 9, 2012 4:59:44 AM

I recall an issue where the screws used to secure the motherboard to the standoffs were the wrong ones and the heads were too large, causing a short.

I don't much like the backplate touching the case; I would try to eliminate that as an issue by testing with the stock cooler. Or, perhaps an insulating shim to break that contact.

There was a case where the front panel was not properly grounded. Try mounting in the case without using the front panel leads at all, and powering on without them.

A stretch.. Are any of the psu cables frayed causing a short in the case?

A DUH.. you unplugged the psu and perhaps turned the switch off before mounting in the case. Is the psu switch back on?
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May 9, 2012 4:24:55 PM

Thanks for all the replies! I'm gonna sort through the info and try you guy's suggestions. Well, first I'ma eat lunch. Work on it, and then update the thread with my results.
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a c 84 B Homebuilt system
May 9, 2012 4:35:53 PM

Added thought: Is it possible that the psu has a short to it's own case?
When mounted in your case, such a short would then transmit to the motherboard, while not installed nothing would happen.

If you can, test this out by leaving the psu out of the case not touching anything and installint the motherboard in the case.
Or.. the reverse, by mounting the psu in the case a d leaving the motherboard outside. Then attach a ground wire from the case to a ground on the motherboard.
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May 9, 2012 4:59:28 PM

Maybe also try mounting it without the board's I/O backplate. Those things seem real finicky.
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May 9, 2012 11:41:03 PM

Okay. Got it all sorted. The first thing I did, since everything was already fastened in the case, was to disconnect everything except the the CPU supplemental, and the 24 pin ATX. I pressed power on the MOBO, and voila!

So, from there I began plugging in one cord at a time, and doing a test boot after each connection. I did this several times, successfully. Then whaddya know? It was the fan controller cable causing the short. I tried unplugging and replugging the molex connectors, but to no avail. The pins for the controller aren't bent, so hopefully it's just the cord and asrock won't mind sending me a new one.

I've gone ahead and just wired the fans to the PSU, but, that's a bit urban for my tastes. I got windows, windows updates, and driver updates installed. No games, unfortunately, I'm tired, and hungry, and that's all for tonight!

Thanks everyone who chimed in!
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a c 84 B Homebuilt system
May 9, 2012 11:54:56 PM

Good job!!!
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!