cant reinstall sound drivers

hi i’ve only joined today and already i need your help basically ive just fresh installed win xp pro
sp2 on a friends system all is working well apart from i get a bsod stop error with portcls.sys everytime i try and install the audio drivers!

now i sure im installing the right drivers for the onboard sound i got it off the motherboard website and its specific for that model its a

ecs 761gx-m754 mainboard and the driver is a realtek ac97 3.98.

there dont seem to be any irq conflicts

any ideas anyone please