The same CPU and FPU are sued on the KA630cpu (uVAXII) and in early
microvax3100s so any of them should compare.
Is it possible that someone has overclocked the that uV2000???
FYI: gate leakage would kill the chips not make it run hot. The
usual reasons for hot running are:
Over voltage!
Overclock
Undercool
Excessive bus loads (capacitive or resistive)
Since the machine is a closed system for the most part the first is
most likely and the others are least likely.
I may add that over 60C is way too hot at the heatsink and the die
due to thermal resistance will be hotter.
I'm trying to pull down one of my uV2ks and fire it up.
Allison
>
>Subject: Re: VAXstation/MicroVAX 2000 CPU/FPU overheating?
> From: "Dave Dunfield" <dave06a at dunfield.com>
> Date: Fri, 29 Feb 2008 08:18:31 -0500
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>> I assume these CPU and FPU chips are MOS devices. Is it possile that
>> excessive leakage across the gate oxide layer in some transsitors of that
>> chip would cause it to run hot, but still work? I'm pretty sure I've seen
>> chips that seem to work, but get hot and then stop working, althoguh
>> cooling them with freezer spray keeps them running. And these were not
>> chips driving high pwoer laods -- they were things like the clock/timer
>> microcontroller in a VCR.
>
>Yes, I'm wondering if it's something like that, however how likely is it
>that both devices would experience the same fairly-uncommon failure mode
>at the same time?
>
>Perhaps I've been engaging in the persuit of an undomesticated ornithoid...
>
>Is it possible that the devices normally run this hot, and the failure is
>occuring for another reason (possibly a side effect of the heat, as cooling
>them does allow it to keep running).
>
>Allison said "they do run hot" - does anyone know how hot?
>
>I did some further tests last night - I dug out my thermocouple and made
>some actual heat measurements with the system assembled, but with the color
>frame buffer removed - there should be better airflow, and this appears to
>be the case, since the machine did not die after 10 minites of operation.
>
>Ambient temp was measureing about 25 degrees C at the start of the test.
>>From power on, the CPU and FPU rose rapidly (within 3-4 minites) to
>the 70C range, then more slowly rose to temperatures of 76C for the CPU
>and 82C for the FPU after 10 mins. At this temperature they seemed to be
>getting stable - having done nearly 1-1/2 mins without an increase. It's
>possible/likely that they would climb anothe few degrees in extended
>operation.
>
>Once this temperature was reached, I held the system in RESET, and
>observed that the temps dropped back after a few minites to about 64C
>for the CPU and 68C for the FPU.
>
>To my mind, a processor running at 80C is damn hot - most of the embedded
>devices I work with list absolute maximum running temperature as 70C or
>75C - but perhaps the DEC devices are designed to run hotter - I note the
>Intel 486 datasheet lists absolute maximum (under bias) as 110C ...
>
>Anyone on the list with a VS 2000 or uVAX 2000 that can do some temperature
>measurements?
>
>Dave
>
>--
>dave06a (at) Dave Dunfield
>dunfield (dot) Firmware development services & tools: www.dunfield.com
>com Collector of vintage computing equipment:
> http://www.classiccmp.org/dunfield/index.html
Does anyone know when seven segment displays first appeared on the scene?
Presumably the first ones were VF, and LED came later?
(I was just looking at a museum's mock-up of the Apollo mission control
console, and the fake readout is made to look like a 7-seg display; I'm just
surprised that the digital readouts weren't all Nixie-based back then)
cheers
Jules
It used to be you could go to Radio Shack and pick up a couple of 74ls02
chips as needed. Now it seems there isn?t a source for someone who wants to
purchase a handful of 74xx ttl chips. I have a ?brand new? s100 SIO card
that is just missing the 14 logic chips to go in the sockets, but I am not
finding a convenient source for them.
Anyone know where I can go to find them in very small quantities?
Jeff Erwin
I recently bought another HP Integral on E-bay, and after the normal
cleanup on the floppy drive it works fine. The expansion slots both
cotnained boards, one was a 512K RAM board, the other an RS232 oard
(which is the main reason I watned this machine!).
Anyway, the RAM board was clearly identical to the 1M board, just with
only have the RAM chips fitted and the links set differently. Having got
a lot of 41256 chips on old PC memory boards, I spent the afternoon
upgrading it to 1M.
BAsically :
1) Remove the bracket and cover from the PCB (torx screws)
2) Clean out the holes fro the RAM and their decoupling capacitors using
a soldering iron and solder sucker. Test the board at this point, if it
doesn't work, find the solder bridge between traces in the RAM area...
3) Fit 16 off 16 pin turned-pin sockets to the RAM space. Test again
4) Fit 16 off 0.1uF capacitors. I found the exact part at Farnell.
They've been discontinued (They're not lead-free...) but they still had
stock. Test again
5) Plug in the RAMs and test again
6) Removce the link 'W2' on the board (this is the bank select line to
the RAM controller), link the end that's common with W1 and W3 to +5V
(e.g. the end of the decoupling capacitor right next to that point). Test
again. You're now using the new RAM chips only, as a 512K oard.
7) If it works, set all the links as for a 1M board, trst again
8) Finally put the cover and bracket back on.
Now for the curiousity. One one of the standard disks supplied with the
Inegral is a program called 'status'. And one of the things it displays
is the amount of free memory.
In my machine, wioth no RAM boards fitted. there's 264K free. With the
512K board, it reports 764K free. And with the 1M board, 1264K free.
My question is what's happening to the other 12K of each half-meg? Or
deos 'status' have an odd definition of a kilobyte?
-tony
I stopped holding my breath for creation of a Q-Bus IDE
controller a long time ago. While I like to think that I
do a reasonable job troubleshooting some problems,
I'm definitely not a hardware/software engineer.
It would have been nice, but it makes more sense
these days to go Q-Bus to SATA. I would imagine
that it would be alot less hassle, and certainly alot less
real estate on the board, with the smaller connectors,
and fewer traces.
At any rate, back to the topic, Q-Bus to Compact Flash.
If you can do Q-bus to Compact Flash, then you can do
Q-bus to IDE, because CF *is* an IDE interface.
Those wonderful CF to IDE adapter boards generally don't
have any circuitry on-board, except to drive status LED's.
Right now, I have Compact flash / IDE on my Q-bus,
albeit in a round-about way.
I have older CMD SCSI controllers (CQD-200's).
Attached to those are ACard 7720U SCSI <> IDE adapters.
http://www.acard.com
The CMD controllers don't have any problems with them,
and it seems to be happy with older IDE drives that I've tried.
And finally, I have ACS IDE <> Compact Flash adpaters.
http://www.acscontrol.com
You can use any IDE <> CF adapter you want,
and you can certainly get them alot cheaper elsewhere.
I chose the ACS unit, since they were one of the few
that I could find that offered it in a 3.5" drive frame.
They also offer them in a 5.25" form factor, but I think
they're just using a readily available 3.5" to 5.25" frame.
I use a SCSI removeable chassis, so I had to modify my
Acard 7720U in order to fit everything into the tray.
There is at least one vendor that offers a direct
SCSI to CF adapter, but they were a bit pricy
compared to my homebrew version.
I have tested my configuration with CF cards
ranging from 4MB up through 2GB, and find
that it works adequately for my needs.
I could see no discernable speed increase between
using real SCSI drives, and the IDE <> CF adapter,
although I wasn't trying to do any significant benchmarking.
(The CQD-200's are kind of poky controllers anyway,
so this didn't really surprise me.)
Now, if I only I could use PUTR to dump a disk image
onto a RAW IDE device, I'd be a happy camper. . . ;-)
T
anyone do or know of anyone doing repairs on vaxstations?
is this a lost art, and I should just buy another one off ebay or what?
I'd love to find someone who did hardware repairs/engineering for dec or still knows the stuff.
Thanks,
Dan.
_________________________________________________________________
> You could have, for example, four RL02s each capable of being
> assigned a "pack" from the card.
> What were the biggest non-MSCP-attached drives?
> How hard would they be to emulate?
While RL02's would probably be easy to emulate,
at 10MB a pop, you don't get alot of bang for your buck.
Note that some operating systems only support 4 drives
per controller, so that will need to be a consideration
as well, when drives are being partitioned.
Note: The capacities mentioned below are approximations.
The largest non-MSCP drive that I'm aware of is the RP20, at 929 MB.
However, I think that was only supported on the KL10. ;-)
For the rest of the world, you'll be looking at MASSBUS devices -
The RP07 is next in line at 504MB, but not supported by all operating
systems.
The RM05, at 256MB . . . definitely supported by RSTS/E;
not sure about smaller operating systems like RT11 though.
I think the RP06 was something like 176MB, although you're still into
MASSBUS.
Once you move below the MASSBUSS level, I think you're looking at an
RK07,
which is what? 25 or 26MB ?
I'm sure someone may chime in with more. . .
T
Hello all,
as I'm trying out some "new" old computers I got during the last few weeks, I'm of course encountering new problems. I have spent some time with search engines without major success, so I figured it would be okay to ask here.
Case one concerns the SGI O2 workstation. I pulled three of those out of a dumpster; they only had a piece of the blue case plastic left on top and the base trays were broken as well - even the CD bezels are missing. The chassis look pretty battered but the machines power up, play their happy notes and enter the resident menu. Each has one disk tray but the disks were probably ruined by being flung into the container. They also all have an A/V module with the O2cam connector in the back panel. The connector is broken in one of them and I'll probably remove it altogether since I don't have a cam anyway but... the S-Video and Composite I/O jacks in the side panel are covered with a square sheet of textured self-adhesive plastic. The PCB silkscreening states they are Moosehead A/V modules and it looks like no major components are missing from the boards so I hope the video I/O will work once I pull the stickers off?
TIA,
--
Arno Kletzander
Student Assistant // Studentische Hilfskraft
Informatik Sammlung Erlangen
www.iser.uni-erlangen.de
Ist Ihr Browser Vista-kompatibel? Jetzt die neuesten
Browser-Versionen downloaden: http://www.gmx.net/de/go/browser
At 9:26 -0600 2/29/08, Dave wrote:
>Yes, I'm wondering if it's something like that, however how likely is it
>that both devices would experience the same fairly-uncommon failure mode
>at the same time?
I'm chiming in very late and probably not very helpfully, but is
there any way a decoupling cap in the vicinity of the FPU/CPU could
either load them or generate heat itself by beginning to short to
ground? My only VAX (4000VLC) had a fault like that in the reset
circuit which would sometimes hold it in reset, as you may remember
>from a couple of years ago.
--
- Mark, 210-379-4635
-----------------------------------------------------------------------
Large Asteroids headed toward planets
inhabited by beings that don't have
technology adequate to stop them:
Think of it as Evolution in Fast-Forward.
> Date: Thu, 28 Feb 2008 19:51:10 +0000 (GMT)
> From: ard at p850ug1.demon.co.uk (Tony Duell)
> Subject: Integral RAM upgrade
> To: cctalk at classiccmp.org
> Message-ID: <m1JUomf-000J3kC at p850ug1>
> Content-Type: text/plain
>
> I recently bought another HP Integral on E-bay, and after the normal
> cleanup on the floppy drive it works fine. The expansion slots both
> cotnained boards, one was a 512K RAM board, the other an RS232 oard
> (which is the main reason I watned this machine!).
>
> Anyway, the RAM board was clearly identical to the 1M board,
> just with
> only have the RAM chips fitted and the links set differently.
> Having got
> a lot of 41256 chips on old PC memory boards, I spent the afternoon
> upgrading it to 1M.
>
[snip]
>
> In my machine, wioth no RAM boards fitted. there's 264K free.
> With the
> 512K board, it reports 764K free. And with the 1M board, 1264K free.
>
> My question is what's happening to the other 12K of each half-meg? Or
> deos 'status' have an odd definition of a kilobyte?
>
> -tony
>
Don't know where the 12K is going to - maybe address space reserved for
I/O - but I have to say I was extremely impressed by the upgrade -
almost exciting reading!
