[weblacky]

Octane serial ports are on the rear (under keyboard and mouse PS/2 Connectors). Lookup the Octane manual for info on pinouts required to establish a terminal with it. ALL SGIs output serial info of some sort while booting, but many stop if there is a keyboard and mouse attached because they assume you have a monitor. If you remove the keyboard and mouse and just have serial, chances are good you'll get full output and can see where it's stopping you.

Yes ,the RED error LED should turn off once done with startup tests and into the PROM. Several things are possible right off the start.

If you have an OLD revision Octane mainboard you cannot use more than 2GB of RAM and you CANNOT use high density RAM made for later Octanes. So if you just got RAM...REMOVE and put back what was there. You can insert the peripheral modules assembly in upside down! Make sure it's Right side up (A towards the top), and finally a bad RTC battery could be stopping you as well during first power-on (but I'm not 100% sure on Octane).

The serial console will tell you more.