Notes of M571     2011/02/05, Updated 2011/03/13
by CW Cyrix

These are things that I found out by Internet surfing and experimenting with my
own motherboard.

1. The J1 Pinout
  A. In the manual, J1 is the Override Power Switch.
  B. You can use an ATX power switch in place of a jumper if you were switching
     from an AT power supply to an ATX power supply.
  C. J1 has 4 pins: 1, 2, 4, and 5.
  D. Pins 4&5, if used, make the machine turn on instantly by use of the
     switch, but require 5 seconds of holding the power button to switch off.
  E. Pins 1&2, if used, make the machine turn on and off instantly by use of
     the power switch. [Discovered this by accident.]

2. The JP5 Setting
  A. If using an AMD processor higher than 350MHz and it is still underclocked
     at 66MHz, you have to set it on 75MHz. A caveat: You need to disable the
     onboard video and get an external video card to do this. [Note: I no
     longer have a Socket 7 CPU faster than that; I just found that info on the
     Internet.]

3. JP3 (Onboard Video)
  A. If enabled, onboard video is inputted through a cable connect to the
     motherboard.
  B. If disabled, an external PCI video card is required for display input.
  C. If you attempt to enable onboard video while having an external video card
     without using the onboard video, the board will sound (if the speaker is
     connected). Nothing will progress after that. [Experiment.]

4. Extra Info - from a defunct website
   http://replay.waybackmachine.org/20051202184354/ [separator]
   http://www.stud.fernuni-hagen.de/q3998142-bin/cgi-bin/pccout.sh#m571
   Special Infos for the M571 :

    * This board is also known as Eurone EM-5571 and Amptron PM9100 (V3.2).
    * There are some unofficial homepages to check.
    * There are three major revisions:
          o V 3.2, minimum CPU-Voltage 2.5V
          o V 3.2A, minimum CPU-Voltage 2.2V
          o V 7.0, minimum CPU-Voltage 2.2V, different I/O chip
    * Certain BIOS-Versions suffer from a *hdd-spindown-problem*.
      Take a look at the unofficial homepages for explanation.
      AFAIK the latest BIOS solved this problem.
    * AMD-CPUs do not work well on this board above 66MHz. VIA/Cyrix do. The
	  reason seems to be the ansycronous mode. I got reports that if you keep
	  the JP5D on clk/2 (1-2), instead of 2-3, as described in the manual,
	  these CPUs will work.
      - BE WARNED, THIS WILL RUN THE PCI AND IDE OUT OF SPEC. USE AT YOUR OWN
	  RISK! -
    * Using FPM the graphics RAM bandwith is limited to 40MHz.
    * Even the latest Bios seems to support only drives up to 32GB.
    * The Chipset supports SDRam up to 64MBit.
	
	My note: Managed to get some 128MB RAM to work on this board. Only one did
	not work so far, and it was a Crucial Micron 128MB RAM stick.