Cpu fan spins on boot Up but fails to stay spinning despite Cpu temps hitting 70°c (system booted prefectly)

[GhostlyPleb]

So I was building a new rig for my girlfriend, I have built two prior systems by myself with no issue but I can't figure this one out. The CPU fan will spin on startup but than refuses to do anything else despite the temps reaching the high 70's. I won't see the computer till the weekend now but i was looking for ideas on troubleshooting. The specs are as follows:

 

CPU: Ryzen 5 2600x

GPU: GTX 660 (temporary, waiting on 1660)

MOBO: B450 AUROS ELITE

PSU: CORSAIR 550W

RAM: CORSAIR VENGENCE DDR4 16GB 3200 (I think)

[minibois]

Is the cooler plugged into the CPU_FAN header? You could try checking the fan curve in the BIOS or possibly connect it to another fan header, to see if possibly the CPU_FAN header is broken

[GhostlyPleb]

1 minute ago, minibois said:

Is the cooler plugged into the CPU_FAN header? You could try checking the fan curve in the BIOS or possibly connect it to another fan header, to see if possibly the CPU_FAN header is broken

It is plugged into the right header and I plugged it in and out to confirm, I tried modifying the fan curve to just operate at 100% but did nothing, I even tried running aida 64 to get the cpu temps up to see if it would get the fan to run but nothing

 

I haven't tried a different fan header I'll give that a try when I'm back out in her place on the weekend. Hope it's not a dead fan because I'm broke as it is