Help with a saturn not displaying video or sound

[Jrussell]

Hey there folks, I managed to pick up a model 2 US Saturn recently and I'm having some issues getting it to work properly.

Day 1 it would take quite a while to display the bios after powering on and would then eventually freeze and go back to no signal after a few minutes.

I recapped the PSU board and since then all I've gotten is no signal. Disc tray doesn't attempt to spin and there is no sound. Voltages coming off the PSU seem correct with 5.2v, 5.2v, ground, ground so I don't think there was actually any issues there. Nothing obviously bad to my inexperienced eye on the main board.

Any advice or theories?

 

[black_kawa]

It need too the 12 volts rail to be working to the system boots correctly. If you can check, check for ripple in the power rails, since ripple can affect seriously the video signal. I recently revived a psu from a Model 2 JP, and using a external power supply, the video signal was very unrealiable.

Alternatively, check the reset signals on the SH2-1 to see if the system is really booting, or have a signal frozen