CPU Fan

[theinstag8tor]

I have a dell dimension 4600 that i had to replace the cpu fan..after replacing the fan still doesnt work..on startup i get a brief message that reads previous fan failure. any ideas?

 

[eagles453809]

....its plugged into the motherboard header right?...if its spinning see if you can ignore the message and boot anyway

 

[theinstag8tor]

it boots but then as soon as the unit heats up it turns off.

 

[mike99]

Try plugging the fan into a different header. If it runs, you have a fault on the motherboard, if it doesn't, you have a faulty fan, RMA and get it replaced.

Mike

 

[DaveF1953]

it boots but then as soon as the unit heats up it turns off.

When you say it boots but as soon as heats up it turns off, do you mean the CPU fan?
Is the CPU fan running all the time. do tou have it on Power saving?

 

[theinstag8tor]

It only has the one header.

 

[theinstag8tor]

When the cpu heats up the machine turns off. The fan doesnt turn at all.

 

[DaveF1953]

When the cpu heats up the machine turns off. The fan doesnt turn at all.

OK - starting from scratch. Are you certain you have adequate thermal paste on your CPU to make good connection to your heatsink? If not, you are touching the two surfaces, yet not letting the heat transfer through. On immediate power up, does the CPU fan spin immediately?
Does it spin full throttle, without any interference slowing it down? You say " when the CPU heats up the machine turns off" How do you know the CPU is heating up? Can you smell it?
Your CPU header is usually a 4 pin header that is keyed to only go in one direction. I hope you are plugging into the right header and the fan is spinning. Just please answer me back on the question - How do you know the CPU is heating up? and Upon initial turn on, is the CPU fan spinning? I know we can get you going if you haven't burnt your CPU.

 

[theinstag8tor]

The cpu fan isnt turning at all. The way i know that the cpu is heating up is that i can use an external fan aimed at the cpu and use the machine as long as i want. As soon as i turn off the fan about 3 mins or so later the machine shuts down.

 

[DaveF1953]

You need a new fan assembly, or, check the fan pins for proper voltage. From the sounds of it, you've solved your problem. Directing air across the CPU keeps it running. Do you have a socket 775 processor? They can be a little difficult to lock down. Borrow a fan and make sure it spins in your header, then buy a good quality fan with Good heat sink compound. You will be very happy, as will I. # minutes of no cooling is destroying your CPU. Stop doing this.

 

[112inky]

Your CPU header is usually a 4 pin header that is keyed to only go in one direction. I hope you are plugging into the right header and the fan is spinning...