This is weird

[demonnn]

my p4 cpu is very loud /hot idle . i went to bios and the temp was 52c and 4000 rpm and it was raising.it's not even hot . the computer is very loud and i can't stand it , it sounds like it's going to explode . 2 weeks ago i opened the front panel and took out some dust from the heatsink with a brush , and i think there is where it started to get noisy. iim gettingnew parts in a week except for the case, but until then i can't use my computer i have netbook that i'm using right now lol which is slow

 

[505090]

use canned air to blow the fans out

 

[Devastator_uk]

It could be the bearings have had it on the fan and a new fan might be required.

 

[Aoster87]

Take the heatsink off and clean it with a brush-tipped end of the vacuum cleaner.

 

[rockyjohn]

All of the above.

When you use the canned air - use it on the entire system including. all intake and exhaust points.
Since it appears to have started when you cleaned HSF - work from that clue:
First replace heatsink fan as noted above - cheap and easy.
Since dust from that cleaning might have caused a problem, blow out the entire case - including the mobo on which dust may have been deposited.
Is there any chance you applied enought pressure whle cleaning HSF to damage the connection between the HSF and CPU?
Depending how mobo fits in case, any chance some metal object was knocked loose and now resides somewhere - such as under the mobo - where it might be causing a short?

 

[demonnn]

i put a small fan in front of the cpu lol ,and it's OK now. Idles at 44c 3000 rpm .
yeah....

 

[4Ryan6]

my p4 cpu is very loud /hot idle . i went to bios and the temp was 52c and 4000 rpm and it was raising.it's not even hot . the computer is very loud and i can't stand it , it sounds like it's going to explode . 2 weeks ago i opened the front panel and took out some dust from the heatsink with a brush , and i think there is where it started to get noisy. iim gettingnew parts in a week except for the case, but until then i can't use my computer i have netbook that i'm using right now lol which is slow

Never clean with a brush, unless you remove the fan and hold it in your hand and get every blade crack and crevice, what you've done is left some dust on it somewhere and threw off the balance of the fan, its the same principle as throwing a wheel weight on a car tire.

 

[demonnn]

yah that was wrong , but oh well I was going to upgrade anyway

 

[Aoster87]

Never clean with a brush, unless you remove the fan and hold it in your hand and get every blade crack and crevice, what you've done is left some dust on it somewhere and threw off the balance of the fan, its the same principle as throwing a wheel weight on a car tire.

I never thought of that, thanks for the tip