[RC5] oddball DES vs. CPU speeds

Remi Guyomarch rguyom at mail.dotcom.fr
Wed Jan 14 23:59:03 EST 1998

linas at linas.org wrote:
> Hi,
> I am seeing some bizarre cracking speeds with the new DES-II cores;
> makes me wonder if there are bugs?  My Cyrix-133 which was much
> faster than my pentium-133 on RC5-64 is much slower on DES.  And
> my PPro-200, which was faster than both pentiums combined, is only
> a little bit faster now.
> Specifically,  after doing 1 block (of 2^30 keys) of DES, I get:
> Pentium-133 -- 611kkeys/sec
> Cyrix-133    -- 478 kkeys/sec
> PPro-200    -- 851 kkeys/sec
> This doesn't make sense -- the PPro isn't even running 200/133 times
> faster than the pentium!!!

Yes, with the current core Pentiums are faster than PPro. A 200 MHz
Pentium cracks ~980 kkeys/s when a 200 Mhz PPro cracks ~850 kkeys/s
(test under NT4).
We took the BrydDES core as-is, and it was optimized for the Pentium
(perhaps simply  because its author (Svend Olaf Mikkelsen) had access to
only a Pentium and not a Pentium Pro...).
If someone is foolish enough to convert the BrydDES source code () from
MASM to AT&T by hand (71 KB), or smart enough to design a converter, I
will be happy to try something ;-)

RÈmi		Don't waste your computer's time. Distribute it!
	    RC5 cores source code : http://wwwperso.hol.fr/~guyom001/

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