[net.micro.68k] 68020 clock rate query

wb@zeta.UUCP (Bill Beblo) (10/19/85)

I am currently in the process of looking rather closely at
some of the "workstations" being offered by companies
such as Sun, Apollo, Masscomp, Integrated Solutions, etc.
Most of these vendors offer a system based on the 68020 chip.
Some of the vendors claim their 68020 is clocked at 16.67MHz
while others claim 12MHz.  Although I realize that a faster
clock rate in itself does not guarantee better throughput,
an interesting dispute has developed regarding two of these
vendors.  Vendor A (16.67MHz clock) claims they have made
special arrangements with Motorola and are paying a premium
for 68020 chips certified by Motorola at 16.67MHz.  Vendor B
(12MHz clock) claims that Motorola is not currently certifying
the 68020 at 16.67MHz and that Vendor A is in reality getting
12MHz chips from Motorola, but using only those chips which
they can successfully push to run at 16.67MHz.

I tend to believe that since the clock rate of 16.67MHz
is printed on Vendor A's glossy brochure they are telling
the truth, but Vendor B's claim does not seem absurd.
I'm not an Electrical Engineer so I'm turning to the net
for answers/opinions.  A reply from a qualified party
at Motorola would also be appreciated.

Bill Beblo
Bell Communications Research
290 W. Mt. Pleasant Ave.  Rm 1B-112
Livingston, New Jersey 07039
(201) 740-4421

pavlov@hscfvax.UUCP (840033@G.Pavlov) (10/21/85)

 Hewlett_Packard has released a workstation (HP9000 series 300)that utilizes
 a 16.67 68020 chip.  Since HP is very conservative re hardware, I think that
 the question about "official" vs "unofficial" releases of the chip are moot.
 
         g.pavlov, FSTRF, Amherst N.Y.

chip@cadsys.UUCP (Chip Krauskopf) (10/22/85)

The testing of microprocessors is a very interesting subject.  To be
certified at a given speed the chip must perform at a given frequency and
meet all the stated specs. across a wide temperature range.  It is one
thing for the part to work at room temp, but high temp is another.  I would
find it very surprising for a chip company to sell parts that don't pass
there full test set at some speed as if they did.  Likewise, if they
have 16MHz parts, I would think they would sell them as such!  The only way
I know to "push" a non-full spec. chip is to cool it and/or run at higher
voltage.
-- 
Chip Krauskopf; 386 Design Team, Intel, Santa Clara, Ca.
{pur-ee,hplabs,amd,scquaxd,dual,qantel}!intelca!cadsys!chip


N.B. The views above are personal and may not represent those of Intel.