CPU fan not working

[dennis bollom]

have just got my old pc back out of storage and booted it up and voila XP loaded and works but when I checked CPU fan it was not spinning. The bios says cpu fan speed n/a and chassis fan n/a (although it is spinning ok)
I have a live nf7g mobo
finally it says cpu quiet fan disabled??
as you can tell I am a newbie to all this but can someone assist as I am told not to run pc without cpu fan working

 

[Harvey]

Start by opening up the case to see if the CPU fan is plugged into the CPU fan headers. It may have come loose in transit.

If the fan is not connected, the BIOS would show you exactly what you see.

There may be other fan headers, but only one is labeled for the CPU fan. If it is not clear which it is, check the manual for your motherboard.

Another possiblity is that you've accumulated so much dust that it's stopping the fan from turning so, before you start, get a can of compressed air, or have a vacuum cleaner handy to get rid of the accumulated dust. There will probably be dust bunnies big enough to attack your shoes.

Come back for more suggestions once you've done that.

Hope that helps.

 

[dennis bollom]

many thanks Harvey. after thoroughly cleaning fan it spins by hand quite easily, but when booted up no fan action(I assume it should start straight away) I have a 4 pin connector and is plugged into the fan socket on the mobo
bios states cpu quiet fan is disabled??

 

[Harvey]

I'm not sure what "Quiet Fan" means. It sounds like it could be a setting to reduce the fan speed when the CPU temp drops below a preset level, and if it's disabled, the fan would continue to spin at full speed.

You've confirmed that the fan is plugged in so it sounds like it could have failed. If so, you have two choices:

1. Buy a new HS/F (heatsink/fan) combintation specified for your CPU socket and rated for at least the maximum power dissipation of your CPU. This is the easiest solution and requires the least work because you won't have to think about whether the fan has the appropriate three or four wire speed control, let alone disassemble and reassemble anything, but it is not necessarily the least expensive solution.

2. Remove the current HS/F from the CPU, remove the fan, and find a suitable replacement. This is not difficult, and it could save you money IF you can find a good, inexpensive fan. All you'll need is a phillips screwdriver.

You want a 12 volt fan the same size as the one in your machine that has the same mounting centers and the same four pin connector. If you find an otherwise appropriate fan that doesn't have the right connector, you should be able to cut the connector off the old one and splice the similiarly colored wires on the new fan.

If you can identify the make and model of the original fan, you may be able to search Google find it or cross-references to replacement parts from other manufacturers. You can probably find the fan maker's sticker either on the back of the fan or under any sticker applied by the HS/F maker.

To obtain the same better or better cooling, buy a fan specified to provide the same or greater amount of air movement, usually specified in cubic feet per minute (CFM). A fan with ball bearings will last longer than one with sleeve bearings, and double ball bearings are the best, but you may not need (or want to pay for) one that good. A reasonable fan may cost less than $5.

If you have trouble finding a replacement, come back with as much info as you can provide about it, and someone may be able to help you. For reference, this page on

Whether you reconstuct your current HS/F or buy a new one, before you remount the HS/F, clean any old thermal compouind from the CPU cooling surface. Windex works well for this. Then, apply a VERY thin coat of fresh thermal compound. Arctic Silver 5 is a good one.

If you want more help selecting a new HS/F, give us your CPU model and socket type. If you don't know, just give us the make and model of the motherboard, or, if it's a pre-built machine (HP, Dell, etc.) give us the make and model of the machine.

 

[dennis bollom]

many many thanks Harvey I have removed the cpu to possibly replace the fan BUT how do I remove the amd fan from the actual cpu there appears to be 4 screw holes but I think they are purely guides to insert the frame of the fan?? I have tried to send a photo hope it works and will await your further instructions

 

[Harvey]

Those four screws should also hold the fan to the heatsink on the way through, or there should be other screws, possibly viewed from the other side of the assembly. It's possible that accumulated grunge and heat have stuck them together. They may come apart with a gentle twist

Obviously, the fan and heatsink assembly are separate parts so they have to come apart... somehow.

I hope you don't have to resort to the old engineering rule: "There's no problem that can't be resolved with a big enough hammer."

 

[dennis bollom]

hi Harvey,boy am I learning with your help. I have been able to separate the fan from the heat/s it simply pressed on with a very tight fit now I have plugged the fan only back into the mobo and still no power to fan, does that mean the plug on the mother board is rs or can I plug anywhere else to test if it is working?
I will come back to you on the question of what cpu I should be using once I have the fan problem fixed
by the way I tried to send you an image of cpu but it kept asking for the urrl of the image where do I find that??
once again thanks for your help.we are sweltering in a 40 degree heatwave hows the snow your end??
regards dennis