The board would power on but not POST. It was unresponsive to the power button once powered up, but holding it down for several seconds would cause the board to power off. It was completely unresponsive otherwise.
The problem was solved by removing the heatsink and re-flowing the Nvidia northbridge with a hot-air soldering station. Using an oven to repair this board is not recommended due to the many small electrolytic capacitors mounted on the board.
For kicks, I thought I’d do a basic THD+N test on my Yamaha AX-590. The results are next to stunning – this is an extremely capable unit. The -88 dBV noise floor (measured with shorted input, CD Direct enabled and the volume at -inf) is simply fantastic for a 100 WPC amplifier, and I had to check that my test load wasn’t broken when measuring the damping factor – almost 1000 at 1 kHz!
What a performer! Given the relatively low (about $600 in 1996) retail price of this unit, I did not expect it to perform anywhere near this well.