Hacks and HOWTOs

I will take no responsibilities if you damage something while trying these stuff. It is for informational purpose only.

Repairing a dead mac address

When your Indigo says it has the mac address ff:ff:ff:ff:ff:ff, your EEPROM is dead. Don't panic, it is repairable. In most cases the reason is, that in this Indigo where placed different CPU boards (IP20 and IP12). The location of the address is different between the boards. When you switch from IP12 to IP20, the mac address will be relocated. When you switch from IP20 to IP12, the mac address will be erased. Fortunally, you can set the mac address in the boot prom of an IP12. To repair it, you must do:
Get a IP12 board, make sure to have the same gfx then used with the board or the prom won't come up (or use a terminal).
Put the IP12 and eventually a graphics board in the broken Indigo.
Go into prom -> command monitor.
Set the mac adress with the command #eaddr 08:00:.... (the adress should be on the chassis).
Put the IP20 and maybe the graphics back in your Indigo, boot and you should have a mac address.

Reducing the noise of an R4400 Indigo

After I have upgraded my IP20 with a PM2, it became very noisy. The reason is quite simple, the PM2 is designed for the Indigo2, and therefore the air flow around the heat sink is very bad. So the CPU become very hot, and the temperature sensor on the PM2 increases the speed of the fan. The solution is also simple. Just take the heat sink from the PM1 and put it on the PM2. I placed it with the larger side to the backplane ( 1 2 3 ). For that I needed to break some cooling fins. Don't forget to use some heat paste.

Recovering the prom password

If you still have the root password, you can use the command 'nvram passwd_key ""'. If not, you have to enter dangerous terrain. I did it once, but maybe i was just lucky. Ok, enough disclaimer: Power down the machine, remove the cpu and gfx board. Remove the eeprom from the backplane. It is on the lower left side, socketed and has 8 pins. Put the boards back, power up and go to the prom. Get some doublesided adhesive tape, and put a bit of it on the eeprom. Put a straw or something similar on the other side. While still in the prom, reinsert _carefully_ the eeprom. Now, use the 'resetpw' command to clear the password. Congratulations!

Using IDE drives

Since SCSI drives got more expensive to IDE drives over time, and the indigo SCSI bus is slower then current drives, i bought a SCSI to IDE converter for around 130 US$. After receiving it, i modified my Indigo in order to mount the drive internally. The adapter is too wide to fit horizontally in the drive bay, so i had to remove the three black plastic slides, and mounted the drive vertically on a drive sled. The only caveat is, you have to plug in the power and SCSI plugs manually. The drive was dedected by the prom without problems, and fx could reformat it properly. Pictures? Look here.