WMS 550 Power Supply help needed

[shinynick]

I picked up a WMS 550 "Swingin in the Green" video slot that worked but had no sound. Looking at the Power supply and PCBs I noticed that the -12V LED was not lit on the I/O PCB which made sense as it is needed for the audio.
While testing the power supply I heard a zap and the screen went dark and all LEDs on the I/O board went out. Looking inside the power supply I found some large resistors  and other components with cracked solder joints. one of the 10A fuses under the power supply assembly was also blown. I also found the -12V regulator was toast along with other components in the -12v circuit. I fixed all this and now I get all 5 voltage LEDs lighting up and voltages are correct when I test for them on the backplane. BUT the DS1 LED is also now lit  (was not before) and the machine does not start up at all and has a black screen. From what I understand he DS1 LED signifies a power supply fault - but what is at fault? Is it looking for a sense signal or...?

I know about the ATX conversions but I'd like to repair this P/S if at all possible.

I also found the CPU battery was dead and replaced that as well  (not sure how it was booting before...)

I will also need a RAM clear ship if anyone sells them or if there is a way to get an image of the Eprom I could burn it myself!

Thanks in Advance

Nick in Canada