As I have said before, any blue tant capacitors should be replaced. Even if they are not "shorted", they many not have the required very high resistance to ground. It is possible one or more caps "partially" failed, and now you have a resistor(s), rather than a capacitor, in the circuit. This could be the cause of the low voltage.

I had just this problem with a capacitor related to my DC memory storage. That is, the capacitor partially failed, it became a few 100k resistor (rather than several Megs) and I was draining my back-up battery it just a few weeks, as opposed to a few years.

--- In oberheim@yahoogroups.com , jim finch <jahg88@...> wrote:
>
> Still having a problem with the D3 line on the data buss.Pulled eveything from the processor pcb- nothing shorted to ground.The D3 line only swings to abpout 2.5 volts.I even got a NOS processor. Only thing left is the PROMS or the resisitor arrays.Ever seen PROMS go bad
>