🚀 go-pugleaf

Scott Mordecai <scott@musicman.demon.co.uk> wrote:

>>> ... the main CPU being Cyrix's new M1 5x86 chip.
>>> Should it be reported as being a Pentium,
>>No.
>>> or it is actually a 486 but with heavy duty go faster stripes on it?
>>Yes. You were thinking of the Cyrix 6x86.

>Aha!  I wrongly assumed the M1 was a pentium clone.  Anyone know how it
>compares to a 'normal' 486?  (i.e.  equivalent to a dx4-100, dx4-120, or
>what, or better?)

Well clone is a bit of an odd way of putting it. It appears to be
Pentium class from the figures (maybe 10-20% slower at a given clock
speed for 32 bit software, very similar for 16 bit stuff) for integer
processing. It's not Pentium class for floating point, but I suspect
only 10% of Pentium users would notice this.

Strictly speaking of course, the Pentium is 386 compatible, as is the
486, Pentium Pro, 586, M1, etc. No new instructions (to all intents
and purposes) have been added since 1985.

If it is 10-20% slower than an equivalently clocked Pentium (I'm going
by Cyrix's figures at their web site!) then a 586-100 would be like a
Pentium-85, or maybe a 486DX4-150. Since all these chips are clock
multiplied it's difficult to generalise, and cache performance is very
important (but 256K is probably enough).