🚀 go-pugleaf

In article <1500065@iuvax> bose@iuvax.UUCP writes:
>
>Can anyone give me the details of the NEC V20 chip stuff. I have an XT
>and would like to speed things up a little. Does the NEC chip have
>any incompatibility drawbacks?

   To use it, just pull out the 8088, and plug in the V20, and away you
go.  I had the job done about 4 months ago, and have had no problems
with it.  I have however heard of some incompatablility problems with
it, but these all occur when the software has internal timing loops,
instead of the Dos timer call (tut, tut, non-portable code).  The only
specific instance of this that I know of is LoadRunner (which doesn't
bother me, because it didn't run on my machine without the V20), though
I hear it also affects some other games, one or two HardDisk controlers,
and a few (very few) other things.

                      S. John Banner

UUCP:     ...!uw-beaver!uvicctr!sbanner1
BITNET:   ccsjb@uvvm
EAN:      sbanner1@uvunix.uvic.cdn

When I installed a V20 in my PC, I found that DISKCOPY and FORMAT
didn't work any more.  Since it was an 8Mhz chip, I had increased
the clock speed at the same time and perhaps that was the cause of
the problem.  In the end, the performance improvement was so
negligible (5 or 10% with the standard clock speed) that I decided
to put the 8088 back and buy a "PC Elevator" which is a card with
an 80286 on it.  The V20 with an 8Mhz clock is definitely the most
bang (50% speedup) for the buck (about $25 including crystal).  It
just bugs me when basic utilities don't work.

		-- Mike Gordon	(ihnp4!inmet!gordon)

> 
> When I installed a V20 in my PC, I found that DISKCOPY and FORMAT
> didn't work any more.  Since it was an 8Mhz chip, I had increased
> the clock speed at the same time and perhaps that was the cause of
> the problem.  In the end, the performance improvement was so
> negligible (5 or 10% with the standard clock speed) that I decided
> to put the 8088 back and buy a "PC Elevator" which is a card with
> an 80286 on it.  The V20 with an 8Mhz clock is definitely the most
> bang (50% speedup) for the buck (about $25 including crystal).  It
> just bugs me when basic utilities don't work.
> 
> 		-- Mike Gordon	(ihnp4!inmet!gordon)

DISKCOPY and FORMAT both require that the processor run at 4.77 MHz.
(Timing dependencies involving the disk controller.)  The FAST88 kit
I have gives you a switch to go back to 4.77 MHz for this exact reason.

Clayton E. Cramer

In article <1091@kontron.UUCP> cramer@kontron.UUCP (Clayton Cramer) writes:
>
>DISKCOPY and FORMAT both require that the processor run at 4.77 MHz.
>(Timing dependencies involving the disk controller.)  The FAST88 kit
>I have gives you a switch to go back to 4.77 MHz for this exact reason.
>
>Clayton E. Cramer

Gee, my pclone, which supposedly runs at 8mhz (norton says 1.6 relative
speed, haven't done the math yet) runs diskcopy and format perfectly
fine....in fact, all my utilities (and all my software for that matter)
work fine.  Good thing, too, because I'd have to move a jumper on my
motherboard if I wanted to take it down to 4.77.  Has anybody had
a problem with diskcopy and format not working at 8mhz?

/*  Chris Rhodes / Shooting Shark
 *  Currently cowering behind lll-crg!csustan!guest
 *  real uucp : lll-crg!csuh!shark -or- lll-crg!ptsfa!harlie!shark
 *  My opinions *are* those of csustan!  Yeah, they made me spokesman, ah,
 */ president of the university!  Yeah, *that's* the ticket!

> 
> When I installed a V20 in my PC, I found that DISKCOPY and FORMAT
> didn't work any more.  Since it was an 8Mhz chip, I had increased
> the clock speed at the same time and perhaps that was the cause of
> the problem.  In the end, the performance improvement was so
> negligible (5 or 10% with the standard clock speed) that I decided
> to put the 8088 back and buy a "PC Elevator" which is a card with
> an 80286 on it.  The V20 with an 8Mhz clock is definitely the most
> bang (50% speedup) for the buck (about $25 including crystal).  It
> just bugs me when basic utilities don't work.
> 
> 		-- Mike Gordon	(ihnp4!inmet!gordon)

Please don't blame the V20. Your problem was the speedup to 8Mhz. There are
other chips in your pc that are sensitive to the clock rate and those need
to be replaced as well. You must also be careful of add-on boards. Some of
those will have problems at 8Mhz (Try running at 6Mhz, you might have better
luck.
                     Jeff Denenberg
                     ..!decvax!ittvax!jeffd

In article <1091@kontron.UUCP> cramer@kontron.UUCP (Clayton Cramer) writes:
>> When I installed a V20 in my PC, I found that DISKCOPY and FORMAT
>> didn't work any more.  Since it was an 8Mhz chip, I had increased
>
>DISKCOPY and FORMAT both require that the processor run at 4.77 MHz.

I am running an 8Mhz PC with the V20 and never had a problem running these
utilities or any other program.



-- 
Owen Adair, Digital Signal Processing Lab, Ga. Institute of Technology
uucp ... !{akgua,allegra,hplabs,ihnp4,seismo,ulysses}!gatech!gt-eedsp!owen
Disclaimer: My employer is not responsible for, nor does it care, what I 
	    say here or anywhere else.

I would imagine that the drive controller dependencies mentioned are 
hardware based and an 8mhz clone that can operate at 4.77 or 8 would
have a driver hardware that operates at 8 for sure, and probably 4.77.

However, IBM saw no need to equip their hardware for anything but 4.77mhz.

RPS
homxb!gritz

In article <208@csustan.UUCP> guest@csustan.UUCP (Chris Rhodes) writes:
>In article <1091@kontron.UUCP> cramer@kontron.UUCP (Clayton Cramer) writes:
>>
>>DISKCOPY and FORMAT both require that the processor run at 4.77 MHz.
>>(Timing dependencies involving the disk controller.)  The FAST88 kit
>>I have gives you a switch to go back to 4.77 MHz for this exact reason.
>>
>>Clayton E. Cramer
>
>Gee, my pclone, which supposedly runs at 8mhz (norton says 1.6 relative
>speed, haven't done the math yet) runs diskcopy and format perfectly
>fine....in fact, all my utilities (and all my software for that matter)
>work fine.  Good thing, too, because I'd have to move a jumper on my
>motherboard if I wanted to take it down to 4.77.  Has anybody had
>a problem with diskcopy and format not working at 8mhz?
>
>/*  Chris Rhodes / Shooting Shark

I've got a FAST88 too, which "Norton's in" at a big 1.7 at 7.14 MHz.
How's this?  Your clone probably has two clocks, one for the processor,
one for the rest of the system, hence FORMAT & DISKCOPY run fine.
(It's also possible your clone isn't sensitive to clock speed the way
a PC is.) The FAST-88 on the other hand runs the whole system at the
higher clock speed.

John Allen
=========================================================================
NetExpress Communications, Inc.      seismo!{sundc|hadron}!netxcom!jallen
1953 Gallows Road, Suite 300         (703) 749-2238
Vienna, Va., 22180
=========================================================================

> In article <1091@kontron.UUCP> cramer@kontron.UUCP (Clayton Cramer) writes:
> >
> >DISKCOPY and FORMAT both require that the processor run at 4.77 MHz.
> >(Timing dependencies involving the disk controller.)  The FAST88 kit
> >I have gives you a switch to go back to 4.77 MHz for this exact reason.
> >
> >Clayton E. Cramer
> 
> Gee, my pclone, which supposedly runs at 8mhz (norton says 1.6 relative
> speed, haven't done the math yet) runs diskcopy and format perfectly
> fine....in fact, all my utilities (and all my software for that matter)
> work fine.  Good thing, too, because I'd have to move a jumper on my
> motherboard if I wanted to take it down to 4.77.  Has anybody had
> a problem with diskcopy and format not working at 8mhz?
> 
> /*  Chris Rhodes / Shooting Shark
>  *  Currently cowering behind lll-crg!csustan!guest
>  *  real uucp : lll-crg!csuh!shark -or- lll-crg!ptsfa!harlie!shark
>  *  My opinions *are* those of csustan!  Yeah, they made me spokesman, ah,
>  */ president of the university!  Yeah, *that's* the ticket!

Well, to be more precise, the BIOS of the IBM PC/XT has a problem running
DISKCOPY and FORMAT at speeds other than 4.77 MHz.  I've been most recently
fighting with a clone called Terminator LT that uses a 286 but an XT-like
BIOS (in fact, the serial I/O BIOS code is a copyright infringement on IBM -- 
I'm glad I didn't buy it) and runs at 10 MHz -- and can't FORMAT floppies!
(The company JUST discovered it and is issuing BIOS ROM upgrades!)

Clayton E. Cramer

The problem may be in the BIOS.  I believe that many PC's use software timing
loops to determine system timeouts (e.g. waiting for the disk drive to return
seek complete).  These prevent the PC from becoming hung if a disk drive is bad
but are clock speed sensitive.

In article <6200047@inmet>, gordon@inmet.UUCP writes:
> 
> When I installed a V20 in my PC, I found that DISKCOPY and FORMAT
> didn't work any more.  Since it was an 8Mhz chip, I had increased
> the clock speed at the same time and perhaps that was the cause of
> the problem.  In the end, the performance improvement was so
> negligible (5 or 10% with the standard clock speed) that I decided
> to put the 8088 back and buy a "PC Elevator" which is a card with
> an 80286 on it.  The V20 with an 8Mhz clock is definitely the most
> bang (50% speedup) for the buck (about $25 including crystal).  It
> just bugs me when basic utilities don't work.
> 
> 		-- Mike Gordon	(ihnp4!inmet!gordon)
	Did you check to see if your memory chips were rated at the
new clock speed? They were probably 200 ns chips. I upgraded my ram
to 120ns and the V20 worked fine...

>
>DISKCOPY and FORMAT both require that the processor run at 4.77 MHz.
>(Timing dependencies involving the disk controller.)  The FAST88 kit
>I have gives you a switch to go back to 4.77 MHz for this exact reason.
>
>Clayton E. Cramer


How come the DISKCOPY and FORMAT that comes with the ZENITH Z158 and Z148 
work on those machines?  Both of them have a switchable clock speed (4.77 and
8 Mhz).  I always have the machine running at 8 and have used both programs
without any problems.

In article <208@csustan.UUCP> guest@csustan.UUCP (Chris Rhodes) writes:
>In article <1091@kontron.UUCP> cramer@kontron.UUCP (Clayton Cramer) writes:
>>
>>DISKCOPY and FORMAT both require that the processor run at 4.77 MHz.
>>(Timing dependencies involving the disk controller.)  The FAST88 kit
>>I have gives you a switch to go back to 4.77 MHz for this exact reason.
>>
>>Clayton E. Cramer
>
>Gee, my pclone, which supposedly runs at 8mhz (norton says 1.6 relative
>speed, haven't done the math yet) runs diskcopy and format perfectly
>fine....in fact, all my utilities (and all my software for that matter)
>[...]

A likely reason for one FORMAT to fail is that it was written too specifically
for a 4.77MHz machine.  Programs such as FORMAT are customized somewhat for
different machines that get MS-DOS.  My MS-DOS, for example, is for an 8MHz
Zenith; and FORMAT among others displays a version banner that specifies it
is by and for Zenith machines.

I believe that there are a few enhancements.  Somewhere out there there
is a file that explains the new features of the V20/30.  I will try to
find it.
-Richard

I  have  been  reading  the  stories/theories/ideas  about using an 8Mhz
machine with interest. I suspect (as noted) that the V20 has nothing  to
do  with the problems; I ran a V30 for months in an 8086 machine with no
problems at all (and that with a FORMAT from a  manufacturer  who  would
have been unlikely to do anything clever).

I  suspect that those machines that DO work either have different timing
loops in the BIOS, or they turn the speed down (on  software  switchable
machines)  while  accessing  the floppy disks. Of course, there are also
the hardware problems like DMA overrun....

Incidentally, I have a so-called 'turbo' (software switchable) 4.77/8Mhz
machine. Last night I fitted an LED to show  if  it  was  in  'fast'  or
`slow'  mode  (I  had been having trouble with ill-behaved programs that
turned the speed down without my immediately noticing). Today I see that
whenever I access the floppies (yesterday I only used the hard disk) the
speed light flickers, and goes out if there is heavy floppy activity.

Thought some of you might be interested in this drivel. You  could  type
'n' if not, but it's a bit late now....
-- 
           Bob Eager

           rde@ukc.UUCP
           rde@ukc
           ...!mcvax!ukc!rde

           Phone: +44 227 66822 ext 7589