I have tried in my EXP8449 (ALI M1487/89) board several BIOSes of other boards and I have found that they work with different timmings for the different BIOS settings when using EDO RAM. One board with Fast/Fast settings may be faster than other with Fastest/Fastest settings just because of how the BIOS was programmed. This is the fastest you can run your EDO RAM with each of these BIOSes (cachechk read/write access time in ns):

pci48afa.bin...................................83/51
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Award Plug and Play BIOS Extension v1.0A
486DX-AC-WBc-25/33/40/50/66/80/100/120/133-A2-ZG
03/25/96-ALI-1487/89-2A4KDM29C-00

8449i21.rom..................................83/76
AMIBIOS
EXP8449 BIOS Ver 2.1
41-C100-001107-00101111-101094-ALI87/89-U

8449i23.rom.................................89/102
AMIBIOS
EXP8449 BIOS Ver2.3
41-C100-001107-00111111-101094-ALI87/89-u

ag56s.rom.....................................89/102
AMIBIOS
AMI PnP BIOS Extension V1.0A
AG56S 120795
41-A000-000000-00101111-101094-ALI87/89-E

apio2smc.bin.................................83/51
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Award Plug and Play BIOS Extension v1.0A
486APIO Ver 2.00 SMC665GT
07/23/96-ALI-1487/89-2A4KDE3HC-00

smt4321-22b.bin...........................89/76
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Terminator 486/5x86 PCI-23 ALI&SMC-MC NOV 22,’95
11/14/95-ALI-1487/89-2A4KDSEIC-00

486-al.bin .....................................83/51
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Terminator 486/5x86 system PCI-25 MAY/13/1996
05/13/96-ALI-1487/89-2A4KDSEIC-00

The fastest you can get with FPM is 76/76. Maybe we can say now that a 486 runs faster with EDO than with FPM RAM (at least for the M1487/89 systems).😀

Edited: I forgot it. These results are for this system configuration:
EXP8449 motherboard
AMD 5x86 @ 160 MHz (4x40 MHz)
256 KB cache @ 2-1-1-1
1x32 MB EDO RAM (50 ns)