cpu question?

[Mark Craypo]

What is the difference between the: Intel 486dx4-100, AMD 486dx4-100,
and the Cyrix series of cpu's? Is one faster than the other? For
processor intensive applications (i.e., pagemaker, autocad, etc) which
works best?

Thanks to all in advance.

[Bill Gallagher]

I know the Intel is faster than the AMD (I forget how much, maybe like
10-20%) I have no idea about the CYRIX.

[Michael K. Daly]

Bill Gallagher (wjg...@psu.edu) wrote:

This stems from the fact that the Intel chip has 16k of level 1 (on-chip)
cache, while the AMD only has 8k. Of course, the AMD dx4/120 is
cheaper than the Intel dx4/100 AND outperforms it (though it only has
8k level 1 cache, too).

--
-- Michael K. Daly --------------------------- email: md...@bbn.com --
-- BBN HARK Systems Corporation -------------- voice: (617)873-2835 --
-- 70 Fawcett Street, 14/104 MS 14/1A -------- fax: (617)873-2473 --
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[Tyrone Thompson]

In article <4d3nkb$8...@info-server.bbn.com>,
Michael K. Daly <md...@bbn.com> wrote:
>Michael K. Daly (md...@bbn.com) wrote:

>: Bill Gallagher (wjg...@psu.edu) wrote:
>: : Mark Craypo wrote:
>: : >
>: : > What is the difference between the: Intel 486dx4-100, AMD 486dx4-100,
>: : > and the Cyrix series of cpu's? Is one faster than the other? For
>: : > processor intensive applications (i.e., pagemaker, autocad, etc) which
>: : > works best?
>

>: : I know the Intel is faster than the AMD (I forget how much, maybe like
>: : 10-20%) I have no idea about the CYRIX.
>

>The main difference (from what I have read) is the Level 1 cache
>(on-chip) size and type.
>
>AMD 8k write-through
>Cyrix 8k write-back
>Intel 16k pre Oct'94: write-through
> post Oct;94: write-back
>
>Write-through is slower, since data is written to cache and memory
>before the write operation completes; with write-back, it is written
>to cache, the write operation completes, then the cache writes it back to
>memory. (Someone please correct me if I'm wrong).

>
>--
> -- Michael K. Daly --------------------------- email: md...@bbn.com --
> -- BBN HARK Systems Corporation -------------- voice: (617)873-2835 --
> -- 70 Fawcett Street, 14/104 MS 14/1A -------- fax: (617)873-2473 --
> -- Cambridge, MA 02138 ------------ http://metro.turnpike.net/mdaly --

One addition, Intel supports 2.5X multiplier which may matter if you are
using a VLB system and your video card cannot support 2X 50Mhz, but can go
40Mhz (2X).

Tyrone
--
--------------
thom...@eecis.udel.edu University of Delaware
Tyrone Thompson EE Graduate Student

[Crays Kevin K]

Please note the follow up is to misc.forsale.computers.discussion.

In article <4d3nkb$8...@info-server.bbn.com>,
Michael K. Daly <md...@bbn.com> wrote:
>Michael K. Daly (md...@bbn.com) wrote:
>: Bill Gallagher (wjg...@psu.edu) wrote:
>: : Mark Craypo wrote:
>: : >
>: : > What is the difference between the: Intel 486dx4-100, AMD 486dx4-100,
>: : > and the Cyrix series of cpu's? Is one faster than the other? For
>: : > processor intensive applications (i.e., pagemaker, autocad, etc) which
>: : > works best?

>

>The main difference (from what I have read) is the Level 1 cache
>(on-chip) size and type.
>
>AMD 8k write-through
>Cyrix 8k write-back
>Intel 16k pre Oct'94: write-through
> post Oct;94: write-back

Actually, I think the big difference is that Cyrix has no FPU.

>
>Write-through is slower, since data is written to cache and memory
>before the write operation completes; with write-back, it is written
>to cache, the write operation completes, then the cache writes it back to
>memory. (Someone please correct me if I'm wrong).
>

I could be wrong, but from what I recall, the difference is that when data
is flushed from the cache(that is room is made for incomming instructions),
the data that is being removed from teh Cache is only written to memory
IF it has changed, thus you save time in many cases with this strategy, which
is Write-Back.

With Write-Through whenever data is removed from cache, it is written back
to memory. I think this is basically correct, but if someone who actually
enjoyed Computer Architecture knows better, I'd certainly like to hear about
it. :)

Kevin