Alarm sound stops only when ISA Video card is on board ...
Look for crushed contacts in the AGP slot too. Some poorly beveled AGP & PCI cards will hook the slot contacts on insertion and crush them down enough to cause shorting. The ISA video being there may be allowing it to boot because the system does not initialize the shorted AGP slot.
Recovery from this demands some good effort with precision dental pick type tools and much luck!!
I've salvaged one of two PCI slots that had this problem enough to get the card re-inserted - but this was only possible by inserting a piece of thin (.010") stiff strip of metal sheet in the slot prior to card insertion. This allowed the straightened contact to have no friction from the card during insertion. The the brass sheet metal strip was then pulled out from between the inserted card and the slot.
The slot not salvaged at least was able to have its short elominated to restore booting - just could not use any PCI cards in it after damage.
Recovery from this demands some good effort with precision dental pick type tools and much luck!!
I've salvaged one of two PCI slots that had this problem enough to get the card re-inserted - but this was only possible by inserting a piece of thin (.010") stiff strip of metal sheet in the slot prior to card insertion. This allowed the straightened contact to have no friction from the card during insertion. The the brass sheet metal strip was then pulled out from between the inserted card and the slot.
The slot not salvaged at least was able to have its short elominated to restore booting - just could not use any PCI cards in it after damage.