Sound not working and system hanging at shut down

After switching parts into my new case and hooking up my new PSU I encountered a small problem. My sound doesn't work! The speakers are plugged into my motherboard's audio directly (green to green) so I don't see why there should be a problem. Help me out, I'm really confused :?

System specs:
P4 Prescott 3.0e
Asus P4SD-LA (Oxford)
1Gb DDR-400 RAM
Corsair HX520W
Antec 900 case

Also there is another problem, I noticed that my system freezes every time I try to shut down hanging on the "windows is shutting down" screen. This has happened before with an old Rosewill PSU. I thought it was caused by an underpowered PSU (it only had 16A) because after I put in a new coolmax 18A PSU the problem magically disappeared. But now it is sadly back with my new Corsair PSU. Does anyone know what could possibly be causing this? I think it might be software related but I don't know it's really had me stumped.

Any help is appreciated!

It is a boxed system with recovery tools on another partition. Partition D: is called "HP Recovery"

The sound drivers seem to be in order. By the way my sound device is called "Realtek AC'97" but still not fixed.

Ah, then I am going to need another HDD.

I still can't figure out the sound problem though. I didn't change drivers or do anything related to sound except for unplug and then replug it into the same motherboard. There is only one plug-in (sound-out) and it is in the right one. I didn't hook up the sound to the front audio panel but that shouldn't matter right? I've only hooked the sound up to the motherboard and that is how it has always been.

Yes I put all cards back into the same slots; I only had a NIC and my Video card which is AGP and I put the NIC in the same slot. I tried following the troubleshooter in device manager and it led me to windows update where I found that the express install wanted me to install "Realtek AC'97 Audio". So I try installing it and it says Realtek AC'97 Audio installation.......................Failed!

Could this be my problem?
I'm not sure if this is because I rolled back drivers (which didn't fix it) or it was my problem all along.

Is it possible I damaged something transferring parts from one case to the other? I didn't drop the motherboard nor did I drop anything else.

There are a few things I don't have hooked up because there arent any connectors for it.

Sure, I'll try anything. Other than this there aren't any new problems.

Edit: Perhaps I will just break down buy a sound card and solve this whole issue

Well, somehow my shut down hanging problem is fixed. I don't know how but it's quite nice. I dont have my old case yet it is in my parent's car (go figure).