Going back to my initial Silicon Graphics Indy post, I was able to procure an R5000SC 180mhz and the 2 board XZ graphics option (along with a spare chassis/node board). These 2 components coupled with the 256mb of ram and the Maxtor ATLAS 15k II U320 drive I already owned, I have acquired the "ultimate" Silicon Graphics Indy.

The R5000SC 180mhz CPU board: Silicon Graphics Indy R5000SC 180mhz CPU board

XZ Graphics board: Silicon Graphics Indy XZ board

The problem I was not aware of until I was about to swap my older R4400 cpu is that you need a specific PROM version in order to run the newer R4600 and R5000 CPUs. In checking my PROM, I came across one of the original versions (version 4) going back to 1993: Silicon Graphics Indy Old Prom

In order to use a R5000 in an Indy you need version 11, which as it happens I have in the newer node board from 1996: Silicon Graphics Indy New Prom

In the end I swapped out the ram from my R4400 Indy, put a "new" Maxtor Atlas 15k II 73gb Ultra 320 drive in the R5000 chassis and started a fresh install of Irix. One might ask why I didn't just take the drive out of my old system, the answer is that the R4400 is the MIPS3 generation of CPUs and the R5000 and above is MIPS4 generation. As noted in my initial post, by having an R5000 I can make full use of the nekoware archive.

Performance wise how does it compare?
Integer Performance: 596.206 (R4400) 225.467 (R5000)
Floating Point Performance: 797.860 (R4400) 1053.990 (R5000)

Integer performance is considerably faster, about equivalent of my old AMD Phenom II P920 1.6ghz notebook CPU, but floating point (probably due to half the L2 cache of the R4400) is roughly 24% slower. With most gaming/graphics operations being floating point based one could argue depending on the application a R4400 200mhz model might be faster than the R5000 180mhz cpu.

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