[SOLVED] CPU fan runs at full speed after Dell Optiplex 7050 SFF shuts down ?

[HarrisonHo1209]

I have a Dell Optiplex 7050 SFF PC at work. It has an Intel i5 7500, 8GB DDR4 ram and no dedicated GPU. It's booting from a M.2 NVMe 256GB Toshiba ssd. The other day, the optiplex had a little issue, it wouldn't boot even though the power led on the case was white, the cpu fan was just running at full speed until I saw and smelled smoke and immediately unplugged the power cord. I reported the damage to the IT department in my company (pretty obvious that I don't fix computers for a living).

A month later, they came back with the same pc. The IT guy said that the CPU fan was broken and "fixed it". They mentioned that the cpu fan would run at full speed once it powers down and said that the cpu fan would act normally when power is on. And sure enough the cpu fan was running at full speed once I shutdown the system and was normal whenever it was on. I was curious and tried to clear the CMOS by powering down the pc, removing the power cord, holding onto the power button for 1 minute, then removing the motherboard battery for 10 minutes. However, after putting it in again, the pc acted the same.

I went to the BIOS and checked the BIOS logs and I saw CPU 0 fan failure. Since this pc has been bought for some time, the Dell warranty has expired for a long time. I was just wondering if anyone would know how to fix this issue? Or should I just tell my boss to send this system off to a permanent retirement ?

 

[Eximo]

Don't really see the need, just connect the computer to a power strip and turn it off everyday.

Likely a motherboard problem. If the fan or RPM sensor were the issue it would stay at full speed all the time.