bought a simple LSI PCI-X card and connected a SATA SSD to his old SGI!
It only works in the Fuel/Tezro/Origin 3x0 machines, but hey, it's something!
FWIW, I just did this recently in an Origin 350. Works great; speeds are pretty excellent:
#---------------------------------------------------------
# req_size fwd_wt fwd_rd bwd_wt bwd_rd rnd_wt rnd_rd
# (bytes) (MB/s) (MB/s) (MB/s) (MB/s) (MB/s) (MB/s)
#---------------------------------------------------------
16384 91.39 271.36 60.61 162.03 20.37 29.58
32768 77.54 251.59 61.02 145.73 40.54 55.43
65536 275.38 209.11 255.17 69.88 239.96 96.22
131072 274.30 212.25 256.30 85.60 259.20 122.00
I did a fresh install with both the SATA SSD and a SCSI HD in there. You have to use the SCSI HD as the boot partition -- or, I believe, load the kernel via bootp() which I haven't done yet but I intend to try. I don't see why it wouldn't work. I partitioned the scsi drive so that inst would have something to copy the install onto, and then once I was in inst I dropped to the shell, used fx to partition the SATA drive (since it was visible at that point), and then in inst swapped mounts so that /usr was the SSD. That way I installed to the SSD from the start.
I made a more detailed writeup here:
LSI SATA in Origin 350 - HackMD
Note I didn't have to do any firmware downgrading; maybe I got lucky? I had firmware version 1.26.0.0 on a SAS3041X-R.
Edit: the SSD itself is a 500gb Samsung 840 EVO I had laying around.