BIOS Setup Modifications
Release 4.0
o Readded Turbo LED flashing when the system is in a power saving state.
o Reinstated the Hard Disk Pre-Delay feature.
o Added ATAPI code to allow CD-ROM boot.  CD-ROM as first boot device option only.
o Fixed problem where CPU Auto HALT features were incorrectly being disabled.  The
  fix results in about 5 watts of additional power saved during CPU inactivity even
  when APM is disabled in setup (as long as a power driver is installed).
o Added call to detect serial mouse if a PS/2 mouse is not installed in the system.
  Will now wake the system if a serial mouse is installed and a PS/2 mouse is not
  installed.
o Fixed problem in which not all resources disabled if all resources cannot be enabled
  for a PCI device.
o Fixed timing loop in keyboard controller related code that was causing problems with
  network remote diskless boot.
o Set Input attribute in Keyboard device node.
o Set IPL attribute in Floppy and IDE device nodes.
o Corrected IRQ programmed for 3F8,IRQ 3;  2F8,IRQ 4;  3E8,IRQ 3; & 2E8,IRQ 4.
  Programming IRQ 3 & 4 reversed.  3F8,IRQ 4;  2F8,IRQ 3;  3E8,IRQ 4;   & 2E8,IRQ 3
  were programmed correctly.       
o Corrected problems and potential problems possibly causing CMOS corruption.  Battery
  failure status was not being preserved through POST.  Date and time could be set to
  default (01/01/90) without posting an error.  Accesses to enable or disable NMI were
  not followed with a read or write.
o Re-enabled palette snooping for those PCI BIOSs that disable it during initialization
  and request palette snooping be enabled via setup.
o Corrected floppy function 08, Return Disk Parameters.   It returned wrong parameters
  if the drive number was illegal.
o Fixed bug in which BIOS text string could be displayed incorrectly. 
o Disabled Hotkey 6 in the Phoenix Keyboard Controller. It's default is enabled and set
  to the Break Key.  This caused problems with some software. 
o Added an additional test on the boot record (test for 0000 at the start of the record)
  to avoid trying to boot from a non-system disk.
o Updated the ATA/ATAPI detection code to be more robust.  Handles faster CPUs, more
  reliably detects CD-ROM drives, and handles IDE drives which act as master and slave
  when no slave exists.
o Fixed Int 15 Function C7h where bogus amount of memory could be returned.
o Fixed password problem in which the password is entered followed by a backspace is
  considered valid.
o Fixed possible Gate A20 enable/disable race condition.