I've battled with the STTNG intermittent reset problem since I've had this pin, up until 16 months ago, when I installed rkahr's daughter board. That solved the problem up until the last few months. It started taking about 2 or 3 minutes after turning on the machine for it to boot up. D19, D20 and D21 would start out, then dim and eventually get enough power to initialize the mpu. Afterwards it would play fine. In the last month the occasional resets have come back.
Last night I started up a great Borg Multiball and the pin reset. Afterwards the pin would start resetting even if I pressed the flipper button in attract mode. I noticed that LED1 on the power board dims when I press the flipper button in attract mode, and the pin reboots.
Now, taking rkahr's board out of the mix, the pin boots right up, without any delay at all. But the attract mode reset still takes place. With the daughter board installed it takes 2 or 3 minutes to boot up. So, I've taken the daughter board out.
Here's my voltage readings on the power board in attract mode:
TP1 - 11.81
TP2 - 4.81
TP3 - 10.10
TP6 - 75.1
TP7 - 22.1
TP8 - 16.7

I've gone through all the z-connector, reseat ribbon cable, attempts, pinwiki research, etc.
I must be getting a voltage drop when anything tries to take some voltage.
Can anyone point me in the right direction? So many BR's and caps, I'm not sure what I should focus on first.
I'd sure appreciate it if anyone could help me figure this out.
Thanks!

My STTNG is back up and running beautifully! Sent the power driver board off to Clive at Coin-Op Cauldron. Clive found lots of stuff to clean up and repair. He cleaned up some prior hacks and did a complete overhaul. The board came back from him looking factory! Great job, Clive!!!
Plugged it up and verified all connections (did I tell you there's lots) and fired it up. Game came back to life and plays like a scalded dog!
I'm in love with this machine again.

Cheers!