Sound device

Hey guys,
My father's computer wasn't working properly so i formatted the disks and installed windows xp.The computer is running ok,except 2 things.
1.The windows did not detect any sound card,so it says no sound device detected!I know it is realtek but i don't have any CD with drivers for it and i tried to get some drivers online but it did not work.Even if i installed it nothing happened and it still says the same-no sound device detected.I found out that the motherboard should be asus AK32.But it is not laptop.
2.There is a main hardrive devided in 3 parts-C,D,E which is ok and then other hardrive which is big one 500GB(i did not formatted this one)but the new windows does not recognize it because it doesn't show that it is there.When I go to bios i can see it is there as a second hardrive but for some reason when i get to windows it's like it doesn't exist.
Does anyone know what to do?
Thanx for any advices.