[Gerry_MAN]

Try the new firmware for your V5.0.
I have two red V5.0 PCB's as well: It turned out i was still using FW 4.6 on my Challenge S and the other one in my Indy had FW 4.8.0.

Flashed my Challenge S to 4.8.1 and devices attached to the external SCSI connector are now recognized and functional, though i haven't done extensive testing.

Ok,
Looks like I had a few Curve balls tossed at me...
These are probably very unlikely events for others to experience...but who Knows.

Long story short....SUCCESS!!  
I managed to sort out the issue and got the SCSI2SD adapter working and have IRIX 6.5 installed and up and running!!




I upgraded the SCSI2SD board firmware....but I still ended up with the same BUS errors as before.  Hmmm...  :dodgy:

I then thought that perhaps my microSD card was bad?... so I swapped the SAMSUNG SD card out for a Lexar Hi-speed microSD XC 64Gig card.
I also attached a SCSI Terminator to the unused external SCSI port, thinking that perhaps the terminator on my internal Ribbon cable was bad.




Anyhow,
I made these changes and this seemed to do the Trick.  Everything installed Flawlessly over the CD-ROM.

I then was taking a couple of photos for this post...to show the SD cards I used... and I discovered that the original SAMSUNG SD card that came with the SCSI2SD board, had physical damage.  You can see how the top edge is broken off!  (Images below.)

 

I was really shocked that this even managed to hold memory at all.  The damage was not noticeable at first, as it's only about 1mm that broke off the edge.
This is quite unlikely to happen to most people....but figured I would share regardless.  Not sure if this arrived like this?...or if I did this unintentionally during the setup?...not sure.


I swapped it out for this Lexar Hi-speed microSD XC 64Gig card...formatted it first...

**************** ATTENTION ******************
MAKE SURE YOU DO A FULL FORMAT OF THE SD CARD!!!

********************************************

Performing a Full Format of the SD card is pretty important....especially if you are repeating the install process from a failed attempt.
If you perform the "Quick Format" option, this will cause issues with the Install, and you can get Volume Header Errors.
So just make sure to perform the Full Format. It can be along wait I know...but will guaranty the install will go smoothly.

So after the full format was complete, I performed the setup with with the SCSI2SD utility program as before.
After that, the IRIX install process was smooth... through and through.



So overall...
Whether the issue was the Damaged microSD card the entire time?.....and perhaps the Firmware update was not needed?....not sure.
Regardless, anyone reading this who is experiencing similar issues.....as a first step....try and SWAP OUT THE micro SD CARD and do a FULL FORMAT...and not a "Quick format!!" remember that.  :@

Anyhow,
I'm just glad it all worked out in the end. 
Now I'm off to debug this Bad Boy....... an Ultra64 Development board!  







Fun Stuff!!

Thanks for all the help Guys!
Cheers!
-Gerry