Hi all, don't really know if it is the right list but I'll give it a shot (sorry for your inconvenient).
I am doing research on different bios chips envolving rewriting of the flash chip. As time goes by, I stumbled into the same problem over and over again (increasing rapidly). At the beginning I thought it might be a Write Protection error but it seems to me that this error is too common to be a write protection kinda crap (as far as I know most of the boards nowadays don't come with write protection enabled by default).
here is a couple of flashrom trys output on different chips:
 
After finding out the right chipset and flash chip:
"Intel ICH5/ICH5R"
"Winbond W49V002FA" (256 KB, FWH) at physical address 0xfffc0000.
I get (about) the same error when trying to write:

ERASE FAILED at 0x00000000! Expected=0xff, Read-0x25, failed byte cout from 0x00000000-0x0003ffff: 0x35e74
ERASE FAILED!
ERASE FAILED!
FAILED!

on most of the time it fails at 0x000000000

About the same error happend on:
"Intel ICH6/ICH6R"
"SST SST49LF003A/B" (384 KB, FWH) at physical address 0xfffa0000

page: 0000 at address: 0x00000000>>>>>>>>>0001 at address: 0x00010000>>>>>>>>>0002 at address: 0x00020000
ERASE FAILED at 0x00020000! Expected=0xff, read=0xdb, failed byte count from 0x00020000-0x0002ffff: 0xfee5
ERASE FAILED!
ERASE FAILED!
FAILED!

Same goes for this one:
"VIA VT8237"
"PMC Pm49FL004" (512 KB, LPC,FWH) at physical address 0xfff80000

ERASE FAILED at 0x00000000! Expected=0xff, Read-0x49, failed byte cout from 0x00000000-0x0000ffff: 0x463
ERASE FAILED!
ERASE FAILED!
FAILED!

Would really like some help,
Thanks ahead!