[rescue] DEC KA730, was Re: Electronics Recycling Day

Steven M Jones smj+rescue at crash.com
Mon Nov 16 16:59:17 CST 2009

Delayed, got my subscribed addresses crossed up...

Sridhar Ayengar wrote:
> der Mouse wrote:
>> Not the 725?  I certainly recall the 725 as feeling slower than the
>> 730, but after this long it's certainly possible that I've got the
>> numbers wrong - or that the speed difference I noticed was at least
>> partly peripheral speed rather than CPU crunch.
> I think the CPU on the 725 is identical to that of the 730.  It's just 
> a different chassis.

Correct, it's the same CPU boardset. But the 11/725 was packaged in a
deskside unit that included an RC25, compared to an 11/730 typically
packaged in a "lowboy" rack with the R80 14" drive. Also I believe you
had one or two slots fewer for RAM in the 11/725.

I don't have the correct DEC handbooks handy, but I'm betting that the
RC25 was a lot slower than the R80. The RC25 was a dual drive unit with
one ~25MB fixed HDD and one ~25MB removable cartridge. The R80 was the
same HDA as the ~120MB RM80 and interfaced directly to a controller
incorporated into the KA730 boardset.

Needless to say, the extra latency of the disk system could make a huge
impact on interactive performance...

Carl R. Friend wrote:
 >   Correct.  The 11/725 was the version sold as OEM gear whereas
 > the 11/730 was DEC's "official" version.

I'm sure DEC was happy to OEM both configurations, but I was not under
the impression that the 11/725 was an OEM-only variant. It certainly 
appeared in one or more of my DEC handbooks as a standard product.

Of course an outfit like ADP would've been the perfect customer to take 
the 11/725 as-is, slap their logo and software on it, and ship it to 
some customers who'd never crack it open...


More information about the rescue mailing list