SE/30 intermittently freezing on the welcome screen

[retrobecanes]

My SE/30 will sometime hang on the welcome screen and this both upon cold starts and restarts. This happens even with extensions off and is apparently not related to the hard drive as I have replaced the hard drive and I was also able to replicate the problem with just an external drive connected. It also happened with both versions 7.5.3 and 7.5.5. When it hangs on the welcome screen, I have to turn off the computer and then turn it back on. It will then usually boot normally. Sometimes it takes two attempts.

 

[unity]

Check the RAM. But I seem to recall someone having this issue a while back and it was the mobo caps. Are the capacitors original or been replaced?

 

[retrobecanes]

Caps have been replaced. How do you propose that I check the RAM?

 

[joethezombie]

I would pull the RAM modules, clean the contacts with an eraser, then replace only bank A.  See if the problem persists.  If so, pull the RAM and put the other set, again only in bank A.  You can also run Ramometer.  Do this to see if you can find a faulty stick by placing a small sticker on sticks that worked with no freeze and/or errors.

I would also check the +5V voltage pin on the floppy connector.  If it gets too low, around 4.6V, the SE/30 will freeze.  There's a good diagram of the floppy port power pins in the Classic Mac Repair Notes on page 9 (figure 5).