On Apr 21, 2021, at 4:25 PM, Dave McGuire
<mcguire at neurotica.com> wrote:
 On 4/21/21 4:05 PM, Mark J. Blair wrote:
  >>
Anyone have an RC25 unit?  I have a few of them in need of imaging up before they are lost
forever...
>
> I do not have one yet, but I would be interested in buying a VAX-11/725 if one came
along at the right price and location. I'm in Riverside, California, USA. I keep
hearing so much ire directed towards the RC25, that I have a sick fascination with
experiencing one for myself, and seeing just how much slower it feels vs. my 11/730.
 The VAX itself won't feel any slower; it's the same board set as the
 11/730. 
 For CPU-heavy stuff, but isn't the RC25 subsystem a lot slower than the RL02+R80
subsystem? See, I need a VAX-11/725 so I can be an expert on this stuff! :) 
 
   Excellent acquisition rationalization. ;)  But yeah, the RC25 is
 noticeably slower than the (already pretty slow) IDC controller that
 handles the R80 and RL02 in an 11/730.  (I had an 11/725+RC25 many years
 ago, and a standard-config 11/730)  I was just thinking CPU differences,
 of which there are none.  Context fail. ;)
             -Dave 
 
 Is that specific to the RC25 controller used on that machine?  On PDP11s, RC25 is an MSCP
device, and I don't remember ever hearing it was particularly slow.  Of course, it was
a pain in the neck with its fixed drive section, but that's a different issue.