Noisy PSU fan at boot up

[PC Lover157]

I have an AMD Athlon X2 machine, with a low-budget 300W PSU.

My problem is that the PSU fan makes a frightening noise when I boot up the computer. A few minutes after the Windows 7 OS loads, the noise fades away.

I attempted to solve this problem by dismantling the PSU (the warranty has ended) and cleaning the fan's bearings with kerosene.

For a couple of days, the boot up was silent. But the noise started to come again!

What is the real reason for the noise? How could I get rid of it?

 

[davcon]

Buy a better psu!
The reason for the noise is the fan bearing is worn out and the psu is probably underpowered.
Sounds like it's on it's last legs.
Replace the psu before it fails.
A cheap psu will likely damage other components when it dies.

 

[PC Lover157]

Buy a better psu!
The reason for the noise is the fan bearing is worn out and the psu is probably underpowered.
Sounds like it's on it's last legs.
Replace the psu before it fails.
A cheap psu will likely damage other components when it dies.

The PSU is rated 300W. I have an AMD Athlon X2 processor, 1 hard disk, 1 DVD writer and on board graphics card on an ASUS MVN DVI motherboard. Is the PSU underrated?

 

[davcon]

The PSU is rated 300W. I have an AMD Athlon X2 processor, 1 hard disk, 1 DVD writer and on board graphics card on an ASUS MVN DVI motherboard. Is the PSU underrated?

I understand your system isn't a powerhouse and a 300W psu is probably all that's required.
But as i've already said chances are the psu is about to give up the ghost.
Why risk your other components for the sake of a troublesome psu?
Plus use lubricating/bearing oil not kerosene if you're too cheap to replace the fan or psu.