it is possible that 5.3 is not booting with firmware from 1999.
At the moment I am replacing a fan on my 43P-140 - so maybe I should liik for newer firmware as well (although this system will never go farther that 5.1).
My first suggestion, thus, is to see if you know anyone who as an older version of AIX - 4.3.3 would be best considering the firmware.
2 5G disks - and firmware from 99 - was a bigish system in it's prime!
---------- Post updated at 03:02 PM ---------- Previous update was at 12:58 PM ----------
When you go to the fixcentral site, there is also a DOS format, that is packaged as a .EXE.
I believe this creates a floppy that can be used to boot and update the system.
If it does not boot, then it is press F1 while booting (or ASCII character 1 when using serial port).
e.g., this .EXE may be what you need:
7043150I.EXE
Hope this helps! (as I am going to do the same, but for the 43P-140 as I mentioned above)
---------- Post updated at 07:55 PM ---------- Previous update was at 03:02 PM ----------
Two problems with the .EXE file.
No longer compatible with a modern version of windows; who has a floppy drive these days - to write the output to?