I've got an RS6K B50, and i've installed AIX 5.3, TL5. It installs fine, the only customisations i make to the BOS are to change the locale / keyboard layout to UK, and to choose not to install graphical software.
I have no video card in this box, and i connect via a serial console (null modem cable) from a sun workstation, it's 25 pin on the sun side, but the B50 only has 9 pin ports so it's 9pin on that side.
The first reboot after install works a charm. I can go through the installation assistant and setup the root password, terminal emulation (vt100) etc.
Every reboot after that will make the machine hang just after the STARTING SOFTWARE announcement, the /|\-/|\ spinner doesn't even get to spin once and just hangs at '-', the LCD shows E140 which is "Loading Operating System". The hard disk light is on constantly, although i can't hear any HD activity.
Any ideas? I'm guessing the hardware's fine due to the install going ok. There is a diag code on power on which translates to either "tampering evident" or "cmos battery dead", i believe the battery is possibly on it's way out as the box does not keep time very well between installs, although it does sometimes.
That old chestnut! I couldn't install AIX 5.1 on my 43P until I updated the firmware on my CD-ROM drive, and I couldn't update the firmware until I installed AIX. I solved that by using yet another CD-ROM drive.
My problem was the 68pin SCSI CDROM needed it's firmware updating.
Open the case, there is an unsupported 50pin SCSI connector on the motherboard. I plugged in a 50pin (SCSI-narrow) CD-ROM, (actually the mechanism from an Apple CD300 with caddy) and was able to install the OS using that.
Once installed, I downloaded the firmware update disk from IBM, and managed to match the IBM CD-ROM to a firmware patch on the disk then followed that procedure. I then proved the system by unplugging the 50pin cable and doing a complete reinstall from the internal drive.