Writing untested since I currently have no possibility to flash the chip somewhere else if it should fail.
flashrom v0.9.5.2-r1517 on Linux 3.2.0-23-generic-pae (i686), built with libpci 3.1.8, GCC 4.6.3, little endian flashrom is free software, get the source code at http://www.flashrom.org
Calibrating delay loop... OS timer resolution is 1 usecs, 2026M loops per second, 10 myus = 10 us, 100 myus = 100 us, 1000 myus = 992 us, 10000 myus = 10170 us, 4 myus = 8 us, OK. Initializing internal programmer No coreboot table found. DMI string system-manufacturer: "System Manufacturer" DMI string system-product-name: "System Name" DMI string system-version: "System Version" DMI string baseboard-manufacturer: "ASUSTeK Computer INC." DMI string baseboard-product-name: "P4G8X " DMI string baseboard-version: "REV 1.xx" DMI string chassis-type: "Tower" Found chipset "Intel ICH4/ICH4-L" with PCI ID 8086:24c0. Enabling flash write... BIOS Lock Enable: disabled, BIOS Write Enable: disabled, BIOS_CNTL is 0x0 OK. The following protocols are supported: FWH. Probing for Atmel AT49LH002, 256 kB: probe_82802ab: id1 0xd4, id2 0x54, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for Intel 82802AB, 512 kB: probe_82802ab: id1 0x00, id2 0xf8, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for Intel 82802AC, 1024 kB: probe_82802ab: id1 0xff, id2 0xff, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for PMC Pm49FL002, 256 kB: probe_jedec_common: id1 0xbf, id2 0x60 Probing for PMC Pm49FL004, 512 kB: probe_jedec_common: id1 0xbf, id2 0x60 Probing for Sharp LHF00L04, 1024 kB: probe_82802ab: id1 0xff, id2 0xff, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for SST SST49LF002A/B, 256 kB: probe_jedec_common: id1 0xbf, id2 0x60 Probing for SST SST49LF003A/B, 384 kB: probe_jedec_common: id1 0xbf, id2 0x60 Probing for SST SST49LF004A/B, 512 kB: probe_jedec_common: id1 0xbf, id2 0x60 Found SST flash chip "SST49LF004A/B" (512 kB, FWH) at physical address 0xfff80000. Lock status for 0x000000 (size 0x010000) is 00, full access Lock status for 0x010000 (size 0x010000) is 00, full access Lock status for 0x020000 (size 0x010000) is 00, full access Lock status for 0x030000 (size 0x010000) is 00, full access Lock status for 0x040000 (size 0x010000) is 00, full access Lock status for 0x050000 (size 0x010000) is 00, full access Lock status for 0x060000 (size 0x010000) is 00, full access Lock status for 0x070000 (size 0x010000) is 00, full access Probing for SST SST49LF004C, 512 kB: probe_82802ab: id1 0x00, id2 0xf8, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for SST SST49LF008A, 1024 kB: probe_jedec_common: id1 0xff, id2 0xff, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for SST SST49LF008C, 1024 kB: probe_82802ab: id1 0xff, id2 0xff, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for SST SST49LF016C, 2048 kB: probe_82802ab: id1 0xff, id2 0xff, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for ST M50FLW040A, 512 kB: probe_82802ab: id1 0x00, id2 0xf8, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for ST M50FLW040B, 512 kB: probe_82802ab: id1 0x00, id2 0xf8, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for ST M50FLW080A, 1024 kB: probe_82802ab: id1 0xff, id2 0xff, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for ST M50FLW080B, 1024 kB: probe_82802ab: id1 0xff, id2 0xff, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for ST M50FW002, 256 kB: probe_82802ab: id1 0xd4, id2 0x54, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for ST M50FW016, 2048 kB: probe_82802ab: id1 0xff, id2 0xff, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for ST M50FW040, 512 kB: probe_82802ab: id1 0x00, id2 0xf8, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for ST M50FW080, 1024 kB: probe_82802ab: id1 0xff, id2 0xff, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for Winbond W39V040FA, 512 kB: probe_jedec_common: id1 0xbf, id2 0x60 Probing for Winbond W39V040FB, 512 kB: probe_jedec_common: id1 0xbf, id2 0x60 Probing for Winbond W39V040FC, 512 kB: probe_jedec_common: id1 0xbf, id2 0x60 Probing for Winbond W49V002FA, 256 kB: probe_jedec_common: id1 0xbf, id2 0x60 Probing for Winbond W39V080FA, 1024 kB: probe_jedec_common: id1 0xff, id2 0xff, id1 parity violation, id1 is normal flash content, id2 is normal flash content Probing for Winbond W39V080FA (dual mode), 512 kB: probe_jedec_common: id1 0xbf, id2 0x60 Found SST flash chip "SST49LF004A/B" (512 kB, FWH). Lock status for 0x000000 (size 0x010000) is 00, full access Lock status for 0x010000 (size 0x010000) is 00, full access Lock status for 0x020000 (size 0x010000) is 00, full access Lock status for 0x030000 (size 0x010000) is 00, full access Lock status for 0x040000 (size 0x010000) is 00, full access Lock status for 0x050000 (size 0x010000) is 00, full access Lock status for 0x060000 (size 0x010000) is 00, full access Lock status for 0x070000 (size 0x010000) is 00, full access Reading flash... done. Restoring PCI config space for 00:1f:0 reg 0x4e