Sun

I recently spotted this SPARCstation 20 on ebay and it looks rather unusual to me. Does anyone here know any more about this particular type of machine (which doesn't appear to be a standard SS20)?

Unlike most SS20s, this one has two 25-pin serial ports on the back (labelled "Serial A" and "Serial B" where my own (more conventional) SS20 has one 25-pin port labelled "A/B". The ebay machine's second serial port is where the 13W3 for the on-board graphics belongs. There are also two unusual external connectors on the back panel where the plates for one MBus and one SBus slot belong. The interior photos show a very different motherboard, too. It's missing the extension on the last two DIMM slots, so it can't accomodate the VSIMMs. Plus, the MBus slots and two of the SBus slots are all blocked by a CPU module with a large plastic shroud. To me, it looks a lot more like an UltraSPARC CPU than any MBus module I've ever seen.

I'm not planning on buying the machine or anything. It's just got me curious as to why it's so different from other SPARCstation 20s that I've seen. Has anybody ever seen one like it? Are the differences purely in appearance or is it functionally different somehow?

By looking closely at the riser for the "mbus" board, you can see the silkscreen 'CYCLE COMPUTER CORPORATION'. They were an outfit that made rackmount SPARC computers and also upgrades for older Sun workstations. (including a SS5 module called the Cycle-5 that you could plug into a SS1, SS2, or even a 3/80). My bets are on it being an UltraSPARC upgrade made by Cycle for the SS10/20.

Seems that Cycle did in fact make UltraSparc upgrades for the Aurora chassis:

http://www.dm-int.com/cycle.htm

Back in the day I really lusted after a Cycle Quad upgrade for my Ultra 2! I had tracked one down once upon a time, but the seller backed out, and I never found one again.

Thanks for the info, guys! I'd never heard of the Cycle upgrades and didn't see their name until robespierre pointed it out. It's certainly some interesting hardware.

ftp://ftp.uni-duisburg.de/Hardware/Cycle/up_20fr.pdf

http://web.archive.org/web/200107220433 ... clecc.com/
http://chiclassiccomp.org/docs/content/ ... grades.pdf