Major Sound problems

I am a novice computer builder. (read I put stuff together and pray)

I put one together for my dad a year ago and everything was fine. It was as follows:

K7N2 (nForce 2 chip set)
athlon 2000xp
Soundblaster Audigy 2
GeForce ti4400
512 MB Kingston ram
Windows XP

It started having corupted video and random crashes while not under load. I assumed it was the video card and replaced it with an old back up with no sucess. Shortly after that the computer would no longer post.

Upon closer inspection under the heatsink it was black kinda like if it was exposed to flame. Anyway after testing the parts in other computers I found the processor and board was toast.

I then bought an ECS KT600-A and another Athlon 2000XP chip and put it all together. At first I could not get it to do anything and then found two of the pins on the wide plug going from the power supply to the MB were blackened. I replaced the power supply and everything booted up fine.

After setting it back up at Dad's the left rear speaker did not play sound and after a short time playing sounds, music, etc wierd scratchy sounds would come from the speakers, then the colors would all mess up on screen, and finally it would crash/reboot.

Figureing the sound card was bad I took it out and installed the AC97 that was on the board. On it the front right speaker will not play and the same other problems above happen. The computer has run for days with sound disabled, infact I am on it right now.

I have been on this thing for weeks and I pride myself on fixing stuff like this, but I fear this time it must be over my head or below my radar. Thank you very much for any help you can give.

Please note It has the same problems with the origional and fresh windows XP install, pre and post SP2.

 

bump incase it was missed.

Please let meknow if more info is needed.

Thank you in advance.