I have a p 4 512 ram 160 sata hard and asus motherbord p48xmx machine. it was a very good machine.but now it is very slow i fomated and reinstall windows few times but it was not succeed.now it take about 10 minits to write a 650 mb cd and about 1and half hourse to write a dvd what can I do to solwe this problem. ram changing and diffraging was also not succeeded. need helpthanks all !

Try to check if the processor cooling is good, the heat sink and fan working heat sink must properly attach to CPU with thermal paste, and check burst capacitor on the board, try to run other hard disk if you have, replace HDD cable and cd-rom cable...

THANK U ! for ur concern. for the moment i have change and check my hard disc ram and prossecer i guess the falt is on the motherbord. so now I need do check the burst capacitor as u said but i dont know what capacitor is that.anyway i will try to check it before change the motherboard. thank u again!

U are correct there were 5 burst capacitors but i dint repair it yet because I doubt that only with a solderin iron I can replace it...

Yes you can replace it, you can use soldering iron to remove it but it easy if you use hot air equipment. Be careful when doing this motherboard has small traces if you cut one of them or scratch then you are out of luck.