New Build boot failure

sasori01

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Jul 29, 2011
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As the title says, my setup only powers for about 2 secs then shuts off. Turns on again by itself and repeats process.

Mobo: MSI P67A-GD65
CPU: Intel i5 2500k
RAM: G.Skill F3-12800CL9Q-16GBRL
PSU: Corsair ax1200

Steps I have tried:
1. Worked through the sticky about boot failure with no luck.
2. Cleared CMOS several times, taken BIOS battery off even replacing it.
3. Short the PSU and it runs continuously without turning off.
4. Down to breadboarding. Setup is on a piece of cardboard (stand offs still there). Tried CPU + CPU cooler still nothing.

No beeps in all tries. LED power indicator goes up to 6/6. Both 24 pin and 8pin are connected to mobo. I'm just at a loss right now :/
 

Paperdoc

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An odd thought: where is the CPU cooler fan plugged in? It MUST be plugged into the mobo port marked CPU_FAN for the mobo to receive the CPU fan speed signal. If it does not, some mobos will shut down VERY quickly in the belief that the CPU cooling fan is not working and the CPU is in imminent danger of overheating. For this possibility, check these items:

1. CPU fan plugged into CPU_FAN port.
2. CPU fan has three wires (red, black and yellow) or four from motor to connector.
3. Connector securely plugged into mobo pinout - disconnect, inspect and re-connect to be sure.
4. If plugging into other fan power supply, go into BIOS immediately on boot and try to find where the CPU Fan is monitored, and see if you can tell it to ignore that fan signal and not send out error messages or take corrective action.
 

rozz

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Sep 18, 2010
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i would also pull any video card and expansion cards on your motherboard (not your RAM). If it boots up, replace them one by one until the problem reoccurs. Once it does, you have found the card giving you the issue.
 

sasori01

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Jul 29, 2011
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CPU fans are mounted correctly and are both plugged in the CPU_FAN port using a Y-splitter. And they do run during the 2 seconds of power up so I think it's not the problem?

I do have the speaker connected yet no beeps in any case. All I have connected are CPU + CPU fans + 1 stick of ram. Also tried with no RAM with no luck. I have reasons to believe the 24 pin connector is the cause of the problem because sometimes I have to wiggle the wire around a bit for it to power up. Any thoughts?
 

Paperdoc

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Having to wiggle a wire to make it work is definitely a clue - no connection should be that flaky.

One obscure suggestion about your two CPU fans on a Y-splitter. Most I have seen ignore a potential problem, and I cannot understand why. When you power two fans via a splitter, it makes complete sense to connect the + VDC and Ground leads (and PWM signal lead on a 4-pin system) in parallel. However, connecting two fan speed signal lines (the yellow ones on 3-pin fans) in parallel means you will send to the mobo two overlapping pulse trains (each has 2 pulses per motor revolution) that are unsynchronized and at slightly different pulse rates. The resulting mess is almost impossible for a fan speed pulse-counting circuit to make any sense of, so the BIOS gets wildly varying results and may end up completely confused. I advocate snipping off one of the two fan speed wires. That way only one pulse train gets to the mobo and it makes complete sense. The downside is that the fan whose speed signal is snipped off will never be monitored, and you just have to check on it occasionally to be sure it is still working.
 

sasori01

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Jul 29, 2011
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I tried to connect 1 cpu fan to the CPU_FAN port and the other to the SYS_FAN1 port and stopped using the splitter but still getting the same results. Tried again this morning and don't have to wiggle around the wire now. Only thing on my mind now is maybe the bios battery provided is not the right kind. It's obscure but that just shows how lost i am >_< messaged MSI 2 days ago but no reply about the problem
 

sasori01

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Jul 29, 2011
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FML bent pin,
IMG_3171a.jpg


It's so hard to take a good picture of it cuz its so small. But you can notice the missing shadow :(
 

Paperdoc

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Putting one of the CPU fans on the SYS_FAN1 port means its speed will be controlled by the temperature at a sensor located somewhere in the mobo, and NOT by the CPU's internal temperature. That is not ideal at all. You would be better plugging it back into the splitter and cutting its fan speed line. If you are not sure which wire that is, post details: are your CPU cooling ans 3-pin or 4-pin. What colour are the wires from the motors?