I have had the Sun Ultra 20 workstation. It's not too exciting because
it's just the Tyan Tomcat motherboard with the original Opteron cased
into nice metal box with the "Sun Microsystems" label. I bought is as
new (it was said that it was the first Ultra 20 in the Czech Republic)
and upgraded it few times (added a graphics board and replaced it
twice, replaced the original 1.8GHz Opteron with the 2.2Ghz dual core
one, expanded the RAM from 512MG to 4GB and replaced the original 80GB
SATA HDD with a pair of 320GB ones) .
It worked well and for a long time (I used it for computations and then
my wife used it as her desktop). Before some years it started to have
issues so I have put it in storage. Now I wanted top revive it but it
seems that the motherboard is dead (it powers up but fans stay on full
speed and there are not further signs of live - I of course tried to
remove and to re-seat everything).
So I should probably start search for a cheap Tyan Tomcat motherboard
now... The case is mostly a standard ATX one so I probably can throw
internals away and put a modern AMD Ryzen stuff here but I wish to keep
this computer as close to original as possible.. The stock tomcat
differs from the Sun version anyway - they removed some ports for use
in the Ultra (all the PS/2 ones, one of Ethernet ports and even the
serial port).
