Fair enough, I know from experience that it isn't a simple swap.....
No chime and the CPU fan going into Lamborghini mode seem to be new issues. A few things you could try:
- re-seating the video card (AGP is really finicky, issues could be caused by the card being on a fraction-of-an-inch angle).
- booting with only one RAM module.
- booting without the SCSI card.
- booting with no drives connected.