Gigabyte 8KNXP Ultra 64

Earlier this year my Gigabyte 8KNXP Ultra 64 (Rev.1) died, now the board supplied by Gigabyte as a replacement is showing the same early symptoms.

The problem first emerged as a sudden power-off. At that stage there were plenty of candidate problems that could have been the cause, so it took some time to finally discover the general cause.

To restart the computer, the power had to be switched off at the power supply, wait for a minute or two, then switch on the power supply then computer power button and off she goes.

Months passed between the first and second incident, but then the period shortened before the motherboard died altogether. By that stage I had eliminated the usual suspects by substituting another power supply, memory and even the CPU.

Today the new board, running fine since July (three months), just did the same thing – it didn’t even last as long as the original MoBo which managed about 6 months before any problems emerged,

I traced the problem of original MoBo to the Intel HR Southbridge chip. This chip feeds the PCI-X slots and Adaptec SCSI chip as well as the sound, USB ports etc.

When the new board arrived, I carefully set it up on a test bench and ran it so that I can measure temperatures. I put all-copper heatsinks on the Southbridge and Adaptec SCSI chips and smaller copper heatsinks on just about everything else. The temperatures came down so I figure that should help extend the life of the board.

Has anyone else had this problem?
Does anyone know a cure?
What MoBo would you recommend for when this unreliable product once again bites the dust?

I have:
Matrox Parhelia Video Card (AGP)
4* 200gig SATA in RAID 0 (Striped)
2* SCSI drives (separate)
2 gig of Kingston DDR I in matched sets of 1gig.
Creative Audigy Sound Card

Are there any compatible boards?

Thanks
Robert