zs01+@andrew.cmu.edu (Zalman Stern) (05/05/90)
1k1mgm@kuhub.cc.ukans.edu writes:
[Comments about cheap R6000 based workstation.]
The vague information I recall is that the R6000 is 5 chips and requires
ECL RAMS for the first level cache. This seems expensive and difficult to
implement in a workstation package. Hopefully, it will drive the price on
R3000 machine down though. I think it is more interesting from the
workstation point of view to think about the next single chip MIPS
implementation (R4000?).
Has MIPS started calling their machines/processors R/?000 or is this merely
a typo picked up from the product name for the IBM RIOS? Until recently, I
always saw R6000 or RC6280 without slashes. It would be nice if we could
keep the MIPS processor as R6000 and the RIOS as RS/6000 so they are easier
to tell apart. (Then again, I hate it when Dow Jones calls Hewlett Packard
"Hewlett" instead of using the whole name or "HP.")
Sincerely,
Zalman Stern
Internet: zs01+@andrew.cmu.edu Usenet: I'm soooo confused...
Information Technology Center, Carnegie Mellon, Pittsburgh, PA 15213-3890cprice@mips.COM (Charlie Price) (05/10/90)
In article <caEYEaS00asBQJoUoq@andrew.cmu.edu> zs01+@andrew.cmu.edu (Zalman Stern) writes: >1k1mgm@kuhub.cc.ukans.edu writes: >[Comments about cheap R6000 based workstation.] > >The vague information I recall is that the R6000 is 5 chips and requires >ECL RAMS for the first level cache. This seems expensive and difficult to >implement in a workstation package. A CPU/FPU requires 3 ECL chips. The CPU is an R6000. The FPU is an R6010 coupled with a multiplier/divider/sqrt chip made and sold by BIT. If you want to build a system, then you might like to have a high-speed bus for CPU/memory/IO. If so, then you would want another Bus-Interface ECL chip designed by MIPS. This bus interface chip is used in the RC6280 system. All of these chips are fabricated by Bipolar Integrated Technology. The processor and bus interface are ECL and talk ECL levels. The cache interface needs to talk ECL levels as well. Moreover, since the machine operates at 67.7 MHz and accesses the primary caches on every cycle, you need reasonably fast RAMs -- something like 7 or 8 ns SRAMS will do. The secondary cache needs to be fairly fast as well. For the RC6280 it is built out of 15 ns SRAMS. The CPU board is hot, but there are other source of heat as well. To get the necessary bandwidth from main memory (CMOS DRAMs) The interleave is high and more of the chips are working at the same time than in a slower system (like the M/2000). This tends to dissipate a lot of power. Altogether, not the sort of thing that is easy to build into a small, quiet, cool package that sits on your desktop. >Has MIPS started calling their machines/processors R/?000 or is this merely >a typo picked up from the product name for the IBM RIOS? Until recently, I >always saw R6000 or RC6280 without slashes. So far, chips are all Rxxxx as in R6000. New systems are RCxxxx or RSxxxx (a workStation) as in RC6280. In the past, systems were named M/xxx or M/xxxx as in M/120 or M/2000. -- Charlie Price cprice@mips.mips.com (408) 720-1700 MIPS Computer Systems / 928 Arques Ave. / Sunnyvale, CA 94086