[SOLVED] PC fans spin up, but no boot. Just built the PC. Is the CPU Faulty?

mikeisdaman66

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Mar 5, 2018
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If it lights up and fans spin up does that meant hat the CPU could be DOA or the motherboard? I know the RAM is functional.
 
Solution
CPU is in the cpu cooler, everything is plugged in correctly. Fans and lights spin up, but no post or beeping,. Could that mean MOBO or CPU?
This is likely to either be a motherboard, GPU or a PSU problem, CPU could also be the problem but it is rare to get a DOA CPU. Could also be the RAM, but you say it is working. That leaves PSU, GPU and motherboard. Have you connected the GPU power connector from the power supply?

If yes, you should try breadboarding the system - take your motherboard out of the case, and plug in only the CPU, CPU cooler, one stick of RAM, GPU and use the PSU to connect the motherboard 24-pin, GPU power and CPU power connectors. Place the motherboard on a cardboard box or a flat non-conductive table. Now...

mikeisdaman66

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Mar 5, 2018
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4,510
Have you checked to make sure all connections are done properly? Plugged in CPU power, GPU power, monitor into the GPU? Make sure your CPU cooler is connected to the CPU_FAN header, and not in some other fan header,
CPU is in the cpu cooler, everything is plugged in correctly. Fans and lights spin up, but no post or beeping,. Could that mean MOBO or CPU?
 
CPU is in the cpu cooler, everything is plugged in correctly. Fans and lights spin up, but no post or beeping,. Could that mean MOBO or CPU?
This is likely to either be a motherboard, GPU or a PSU problem, CPU could also be the problem but it is rare to get a DOA CPU. Could also be the RAM, but you say it is working. That leaves PSU, GPU and motherboard. Have you connected the GPU power connector from the power supply?

If yes, you should try breadboarding the system - take your motherboard out of the case, and plug in only the CPU, CPU cooler, one stick of RAM, GPU and use the PSU to connect the motherboard 24-pin, GPU power and CPU power connectors. Place the motherboard on a cardboard box or a flat non-conductive table. Now you need to short the two pins in the front panel connectors that say power connector or PW_SWITCH. This should turn on the system. See if you get a display now.
 
Solution

mikeisdaman66

Reputable
Mar 5, 2018
22
0
4,510
This is likely to either be a motherboard, GPU or a PSU problem, CPU could also be the problem but it is rare to get a DOA CPU. Could also be the RAM, but you say it is working. That leaves PSU, GPU and motherboard. Have you connected the GPU power connector from the power supply?

If yes, you should try breadboarding the system - take your motherboard out of the case, and plug in only the CPU, CPU cooler, one stick of RAM, GPU and use the PSU to connect the motherboard 24-pin, GPU power and CPU power connectors. Place the motherboard on a cardboard box or a flat non-conductive table. Now you need to short the two pins in the front panel connectors that say power connector or PW_SWITCH. This should turn on the system. See if you get a display now.
GPU, PSU, RAM are all known functioning. If CPUs are rare to be DOA, it's probably the motherboard.
 

GorillaMonsoon

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Feb 29, 2020
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Have you tried doing a warm reboot? As in not turning off the computer completely just pressing reset. If it fixes the problem then the likely culprit is your psu.
Do you have any more info on that? I've had similar issues to the OP with the fans spinning but no post albeit in different conditions like exiting a game for example, but hitting reset fixes it. Just yesterday I was reading about PSUs on this site and apparently my Corsair CX550 (2017) is actually not that great, but not worst of the worst at least.
 

Juan_Bijero

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Jan 22, 2016
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Do you have any more info on that? I've had similar issues to the OP with the fans spinning but no post albeit in different conditions like exiting a game for example, but hitting reset fixes it. Just yesterday I was reading about PSUs on this site and apparently my Corsair CX550 (2017) is actually not that great, but not worst of the worst at least.

I've got a Corsair CX750M (sitting in a drawer. It was trouble so it was quickly replaced