computer acting funny

Hi,
I recently bought a new CPU (Amd AthlonXP 2400+) to replace my old CPU (AMD AthlonXP 1800+)

ever since i installed it, my computer has been acting funny,
she does some operations really fast (like games, and benchmarks) and some really really slow (like decoding DivX/Xvid or even inputing text in websites and notepad)
the text thing does not happen all the time. only sometimes, when the computer is a bit busy, text inputing starts to take its time and even the mouse cursor has delays...

I really dont get it, do i need to install some driver over again? the Via4in1 perhaps ?

any answer would be much abliged

~ where is my translocator? ~

I don't think so but I'l give it a try

~ where is my translocator? ~