> one of my machines is a Cx486-40 with an ISA bus.  It's got a minor problem:
> the internal cache doesn't coordinate properly with DMA, or something,
> so the internal cache must be disabled for the system to work.
> 
  I'm running on Cyrix 486DLC-40 too.  I think your problem is arised by a
non-486DLC aware motherboard.  I am sure there is a program called cyrixtst
on oak.oakland.edu which can detect such problem.  At least, mine is running
as fast as a 486DX-33 except FPU performance.  Of course, it should be much
nicer if I've more RAM but the price of DRAM here will kill me much. :)

-- 
   ________________________________________________________________________
  /             National Chiao Tung University in Taiwan                 / \
 |  Name: Yeng-Chee Su              Dept:  Computer Engineering         |__/
 |  Phone: +886-35-783513           E-mail: yenchee@csie.nctu.edu.tw    |
 |  Address: 22, Alley 2, Lane 173, Gao Tsui Road, HsinChu, Taiwan 300  |___ 
  \______________________________________________________________________\__/

------------------------------------------------------------------------------