O2 RAM upgrade
==============

I am in the middle of testing  of my RAM moduli the Silicon Graphics O2
system. Once  I had the whole  1 GB of RAM  in my O2 (8  x 128MB). Then
something failed and I ended with just 256MB (2x 128MB).

This is  a problem because while  the IRIX itself (even  in its latest,
greatest  and the  most RAM-hungry  version 6.5)  uses rather  moderate
amount of  RAM (it  is perfectly  happy with 128  MB even  when running
the  Netscape 4.x)  some  of applications  require a  lot  of RAM.  The
Mozilla browser  (the Seamonkey  or the Firefox)  are good  examples of
such  applications  but many  other  (and  more  useful) ones  (3D  and
visualisation packages, FEA tools...) like to eat a lot of RAM, too.

Thus I have decided to try the rest of RAM moduli to find out which are
bat and which are not. One of  sets (they always must be used in pairs)
causes  the poor  O2  to  reboot infinitely.  The  another pair  caused
something like  the "ECC  Error in  DIMM 3..."  message. That  was much
better as it identified a bad RAM stick.


So  I inserted  the  last  available pair.  At  the  first boot  (which
proceeded normally)  the machine tries to  tell me that there  are just
256MN or RAM. So  I halted it, booted once more and  ... the O2 finally
accepted that there are 512MB!


At the  moment I'm running  the computer with  these 512MB. It  is much
better that  just 256MB: I  have opened a  lot of RAM-hungry  stuff and
still see no considerable swapping.


Will report how (if) it develops...


Update: Now I have 768 MB of RAM (so only one pair of RAM is bad):

moose>hinv                                                                   <~
CPU: MIPS R10000 Processor Chip Revision: 3.4
FPU: MIPS R10010 Floating Point Chip Revision: 0.0
1 250 MHZ IP32 Processor
Main memory size: 768 Mbytes
Secondary unified instruction/data cache size: 1 Mbyte on Processor 0
Instruction cache size: 32 Kbytes
Data cache size: 32 Kbytes
FLASH PROM version 4.18
Integral SCSI controller 0: Version ADAPTEC 7880
  Disk drive: unit 2 on SCSI controller 0
	CDROM: unit 4 on SCSI controller 0
Integral SCSI controller 1: Version ADAPTEC 7880
On-board serial ports: tty1
On-board serial ports: tty2
On-board EPP/ECP parallel port
CRM graphics installed
Integral Ethernet: ec0, version 1
Iris Audio Processor: version A3 revision 0
Video: MVP unit 0 version 1.4
AV: AV1 Card version 1, Camera not connected.
Vice: TRE
1600SW Flat Panel adapter board and display.