ruhkus
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CPU_FAN connection not properly working on motherboard - what is best option?
A PC I'm working on was reporting a CPU_FAN error. The fan would spin fine on start up but was very erratic afterwards- resulting in the PC ultimately shutting down. At one point I got it working for a few days, but the second I tried to put on the side panel to the PC (I had left it open), it shut down the PC immediately (I guess it short circuited or something?)
Since then, I connected the CPU fan to another fan connection on the motherboard and the fan appears to spin fine, so I'm fairly certain it's the CPU_FAN connection. Now though, my other fan at the back of the PC isn't plugged in (the cable seems too short to reach the CPU_FAN connection.
What are my best options at this point? Will my PC function if the CPU fan is running and not the back fan? Short of replacing the motherboard, what else can I try?
The BIOS settings seem limited (HP Pro 3500), but I believe some BIOS settings may allow me some additional options, esp. since the fan itself does not seem to be bad.
Since then, I connected the CPU fan to another fan connection on the motherboard and the fan appears to spin fine, so I'm fairly certain it's the CPU_FAN connection. Now though, my other fan at the back of the PC isn't plugged in (the cable seems too short to reach the CPU_FAN connection.
What are my best options at this point? Will my PC function if the CPU fan is running and not the back fan? Short of replacing the motherboard, what else can I try?
The BIOS settings seem limited (HP Pro 3500), but I believe some BIOS settings may allow me some additional options, esp. since the fan itself does not seem to be bad.
rindi
Usually if the CPU fan works, and the one in the PSU, that is good enough. I only use additional case fans for very special situations.
You can power the rear fan from one of the molex connectors on the power supply. Just get a simple adapter cable: http://www.amazon.com/Molex-Computer-Connector-Y-Splitter-Adapter/dp/B00DU8ZZ0O
Be aware that if you're not using the dedicated CPU fan connector, then a failure of the CPU fan would not shut down the PC. It's possible that you could cook the CPU.
Check the CPU temperature warnings and shutdown settings in your BIOS, and maybe disable the CPU fan warnings/shutdown controls.
Check the CPU temperature warnings and shutdown settings in your BIOS, and maybe disable the CPU fan warnings/shutdown controls.
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OK, I tried testing with another cpu fan and that one worked fine. However, it was only 3-pin, so technically I'm not sure if it's the fan or the mobo sensor that stopped working.
However, I also was able to rotate the case fan so the wire was closer to the CPU_FAN connection. So basically I switched motherboard connections for the CPU fan and the case fan. Both are running fine right now. Can I probably keep things this way (both fans running at full speed now), and if a fan fails, still have some assurances of the PC shutting off?
Should I encourage the user of this PC to shut down his computer nightly (or at least every few days) now, as opposed to leaving his PC on 24/7?
However, I also was able to rotate the case fan so the wire was closer to the CPU_FAN connection. So basically I switched motherboard connections for the CPU fan and the case fan. Both are running fine right now. Can I probably keep things this way (both fans running at full speed now), and if a fan fails, still have some assurances of the PC shutting off?
Should I encourage the user of this PC to shut down his computer nightly (or at least every few days) now, as opposed to leaving his PC on 24/7?
you really should test with the correct 4 pin one to be sure imo
the fact that both run fine now only tells me that they have 12 V - and no mechanical problems
i always shut down my pc 3 x per day
the fact that both run fine now only tells me that they have 12 V - and no mechanical problems
i always shut down my pc 3 x per day
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i agree, Gary, i'm only telling him that the only sure way to check if the CPU FAN control on the mobo works is testing it with the proper fan = 4 pin
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