diff --git a/src/acpi.c b/src/acpi.c
index 9521d5337..ddd2ffbe7 100644
--- a/src/acpi.c
+++ b/src/acpi.c
@@ -1669,6 +1669,10 @@ acpi_reset(void *priv)
         acpi_power_on = 0;
     }
 
+    /* The Gateway Tomahawk requires the LID polarity bit to be set. */
+    if (!strcmp(machine_get_internal_name(), "tomahawk"))
+        dev->regs.glbctl |= 0x02000000;
+
     acpi_rtc_status = 0;
 
     acpi_update_irq(dev);
diff --git a/src/chipset/intel_4x0.c b/src/chipset/intel_4x0.c
index 1e4158b94..a1f923e49 100644
--- a/src/chipset/intel_4x0.c
+++ b/src/chipset/intel_4x0.c
@@ -1522,6 +1522,8 @@ i4x0_read(int func, int addr, void *priv)
            with the addition of bits 3 and 0. */
         if ((func == 0) && (addr == 0x93) && ((dev->type == INTEL_440FX) || (dev->type == INTEL_440LX) || (dev->type == INTEL_440EX)))
             ret = (ret & 0xf9) | (pci_read(0x0cf9, NULL) & 0x06);
+        else if ((func == 0) && (addr == 0x52) && (dev->type == INTEL_430TX) && !strcmp(machine_get_internal_name(), "tomahawk"))
+            ret = 0xb2;
     }
 
     return ret;
diff --git a/src/include/86box/flash.h b/src/include/86box/flash.h
index d161d416b..6f0e1ff15 100644
--- a/src/include/86box/flash.h
+++ b/src/include/86box/flash.h
@@ -60,4 +60,6 @@ extern const device_t sst_flash_49lf080_device;
 extern const device_t sst_flash_49lf016_device;
 extern const device_t sst_flash_49lf160_device;
 
+extern const device_t amd_flash_29f020a_device;
+
 #endif /*EMU_FLASH_H*/
diff --git a/src/include/86box/machine.h b/src/include/86box/machine.h
index 9ca9a84be..faed59dae 100644
--- a/src/include/86box/machine.h
+++ b/src/include/86box/machine.h
@@ -680,6 +680,7 @@ extern int machine_at_mb540n_init(const machine_t *);
 extern int machine_at_56a5_init(const machine_t *);
 extern int machine_at_p5mms98_init(const machine_t *);
 extern int machine_at_richmond_init(const machine_t *);
+extern int machine_at_tomahawk_init(const machine_t *);
 
 extern int machine_at_ficva502_init(const machine_t *);
 
diff --git a/src/include/86box/net_pcnet.h b/src/include/86box/net_pcnet.h
index ccdc7e832..23ee643ed 100644
--- a/src/include/86box/net_pcnet.h
+++ b/src/include/86box/net_pcnet.h
@@ -36,5 +36,6 @@ extern const device_t pcnet_am79c960_vlb_device;
 extern const device_t pcnet_am79c961_device;
 extern const device_t pcnet_am79c970a_device;
 extern const device_t pcnet_am79c973_device;
+extern const device_t pcnet_am79c973_onboard_device;
 
 #endif /*NET_PCNET_H*/
diff --git a/src/machine/m_at_socket7.c b/src/machine/m_at_socket7.c
index c26ad3889..46b95ce76 100644
--- a/src/machine/m_at_socket7.c
+++ b/src/machine/m_at_socket7.c
@@ -43,6 +43,8 @@
 #include <86box/fdc.h>
 #include <86box/nvr.h>
 #include <86box/scsi_ncr53c8xx.h>
+#include <86box/thread.h>
+#include <86box/network.h>
 
 int
 machine_at_acerv35n_init(const machine_t *model)
@@ -1046,6 +1048,48 @@ machine_at_richmond_init(const machine_t *model)
     return ret;
 }
 
+int
+machine_at_tomahawk_init(const machine_t *model)
+{
+    int ret;
+
+    ret = bios_load_linear("roms/machines/tomahawk/0AAGT046.ROM",
+                           0x000c0000, 262144, 0);
+
+    if (bios_only || !ret)
+        return ret;
+
+    machine_at_common_init_ex(model, 2);
+
+    pci_init(PCI_CONFIG_TYPE_1);
+    pci_register_slot(0x00, PCI_CARD_NORTHBRIDGE, 0, 0, 0, 0);
+    pci_register_slot(0x0F, PCI_CARD_SOUTHBRIDGE, 1, 2, 3, 4); /* PIIX4 */
+    pci_register_slot(0x0D, PCI_CARD_VIDEO,       3, 0, 0, 0);
+    pci_register_slot(0x0E, PCI_CARD_NETWORK,     4, 0, 0, 0);
+    pci_register_slot(0x06, PCI_CARD_NORMAL,      1, 2, 3, 4);
+    pci_register_slot(0x07, PCI_CARD_NORMAL,      2, 3, 4, 1);
+    pci_register_slot(0x08, PCI_CARD_NORMAL,      3, 4, 1, 2);
+    device_add(&i430tx_device);
+    device_add(&piix4_device);
+    device_add(&keyboard_ps2_intel_ami_pci_device);
+    device_add(&fdc37c67x_device);
+    device_add(&amd_flash_29f020a_device);
+    spd_register(SPD_TYPE_SDRAM, 0x3, 128);
+    device_add(&lm78_device);      /* fans: Thermal, CPU, Chassis; temperature: unused */
+    device_add(&lm75_1_4a_device); /* temperature: CPU */
+
+    if ((gfxcard[0] == VID_INTERNAL) && machine_get_vid_device(machine))
+        device_add(machine_get_vid_device(machine));
+
+    if ((sound_card_current[0] == SOUND_INTERNAL) && machine_get_snd_device(machine))
+        device_add(machine_get_snd_device(machine));
+
+    if ((net_cards_conf[0].device_num == NET_INTERNAL) && machine_get_net_device(machine))
+        device_add(machine_get_net_device(machine));
+
+    return ret;
+}
+
 int
 machine_at_ficva502_init(const machine_t *model)
 {
diff --git a/src/machine/machine_table.c b/src/machine/machine_table.c
index 8a8e1b2ff..7406cce30 100644
--- a/src/machine/machine_table.c
+++ b/src/machine/machine_table.c
@@ -33,6 +33,7 @@
 #include <86box/sound.h>
 #include <86box/video.h>
 #include <86box/plat_unused.h>
+#include <86box/net_pcnet.h>
 
 // Temporarily here till we move everything out into the right files
 extern const device_t pcjr_device;
@@ -10708,6 +10709,46 @@ const machine_t machines[] = {
         .snd_device = NULL,
         .net_device = NULL
     },
+    /* [TEST] Has AMI Megakey '5' KBC firmware on the SM(S)C FDC37C67x Super I/O chip. */
+    {
+        .name = "[i430TX] Gateway Tomahawk",
+        .internal_name = "tomahawk",
+        .type = MACHINE_TYPE_SOCKET7,
+        .chipset = MACHINE_CHIPSET_INTEL_430TX,
+        .init = machine_at_tomahawk_init,
+        .p1_handler = NULL,
+        .gpio_handler = NULL,
+        .available_flag = MACHINE_AVAILABLE,
+        .gpio_acpi_handler = NULL,
+        .cpu = {
+            .package = CPU_PKG_SOCKET5_7,
+            .block = CPU_BLOCK_NONE,
+            .min_bus = 50000000,
+            .max_bus = 66666667,
+            .min_voltage = 2100,
+            .max_voltage = 3520,
+            .min_multi = 1.5,
+            .max_multi = 3.0
+        },
+        .bus_flags = MACHINE_PS2_PCI,
+        .flags = MACHINE_IDE_DUAL | MACHINE_APM | MACHINE_ACPI | MACHINE_VIDEO | MACHINE_SOUND | MACHINE_NIC,
+        .ram = {
+            .min = 8192,
+            .max = 262144,
+            .step = 8192
+        },
+        .nvrmask = 255,
+        .kbc_device = NULL,
+        .kbc_p1 = 0xff,
+        .gpio = 0xffffffff,
+        .gpio_acpi = 0xffffffff,
+        .device = NULL,
+        .fdc_device = NULL,
+        .sio_device = NULL,
+        .vid_device = &s3_trio64v2_dx_onboard_pci_device,
+        .snd_device = &cs4236b_device,
+        .net_device = &pcnet_am79c973_onboard_device
+    },
 #if defined(DEV_BRANCH) && defined(USE_AN430TX)
     /* This has the Phoenix MultiKey KBC firmware. */
     {
diff --git a/src/mem/sst_flash.c b/src/mem/sst_flash.c
index 472a042d1..cd6ec7cd9 100644
--- a/src/mem/sst_flash.c
+++ b/src/mem/sst_flash.c
@@ -131,6 +131,9 @@ static char flash_path[1024];
 #define W29C020     0x4500
 #define W29C040     0x4600
 
+#define AMD         0x01 /* AMD Manufacturer's ID */
+#define AMD29F020A  0xb000
+
 #define SIZE_512K   0x010000
 #define SIZE_1M     0x020000
 #define SIZE_2M     0x040000
@@ -144,12 +147,32 @@ sst_sector_erase(sst_t *dev, uint32_t addr)
 {
     uint32_t base = addr & (dev->mask & ~0xfff);
 
-    if ((base < 0x2000) && (dev->bbp_first_8k & 0x01))
-        return;
-    else if ((base >= (dev->size - 0x2000)) && (dev->bbp_last_8k & 0x01))
-        return;
+    if (dev->manufacturer == AMD) {
+        base = addr & biosmask;
+
+        if ((base >= 0x00000) && (base <= 0x0ffff))
+            memset(&dev->array[0x00000], 0xff, 65536);
+        else if ((base >= 0x10000) && (base <= 0x1ffff))
+            memset(&dev->array[0x10000], 0xff, 65536);
+        else if ((base >= 0x20000) && (base <= 0x2ffff))
+            memset(&dev->array[0x20000], 0xff, 65536);
+        else if ((base >= 0x30000) && (base <= 0x37fff))
+            memset(&dev->array[0x30000], 0xff, 32768);
+        else if ((base >= 0x38000) && (base <= 0x39fff))
+            memset(&dev->array[0x38000], 0xff, 8192);
+        else if ((base >= 0x3a000) && (base <= 0x3bfff))
+            memset(&dev->array[0x3a000], 0xff, 8192);
+        else if ((base >= 0x3c000) && (base <= 0x3ffff))
+            memset(&dev->array[0x3c000], 0xff, 16384);
+    } else {
+        if ((base < 0x2000) && (dev->bbp_first_8k & 0x01))
+            return;
+        else if ((base >= (dev->size - 0x2000)) && (dev->bbp_last_8k & 0x01))
+            return;
+
+        memset(&dev->array[base], 0xff, 4096);
+    }
 
-    memset(&dev->array[base], 0xff, 4096);
     dev->dirty = 1;
 }
 
@@ -262,10 +285,14 @@ sst_read_id(uint32_t addr, void *priv)
 {
     const sst_t  *dev = (sst_t *) priv;
     uint8_t       ret = 0x00;
+    uint32_t      mask = 0xffff;
 
-    if ((addr & 0xffff) == 0)
+    if (dev->manufacturer == AMD)
+        mask >>= 8;
+
+    if ((addr & mask) == 0)
         ret = dev->manufacturer;
-    else if ((addr & 0xffff) == 1)
+    else if ((addr & mask) == 1)
         ret = dev->id;
 #ifdef UNKNOWN_FLASH
     else if ((addr & 0xffff) == 0x100)
@@ -278,6 +305,9 @@ sst_read_id(uint32_t addr, void *priv)
             ret = dev->bbp_first_8k;
         else if (addr == 0x3fff2)
             ret = dev->bbp_last_8k;
+    } else if (dev->manufacturer == AMD) {
+        if ((addr & mask) == 2)
+            ret = 0x00;
     }
 
     return ret;
@@ -300,6 +330,15 @@ static void
 sst_write(uint32_t addr, uint8_t val, void *priv)
 {
     sst_t *dev = (sst_t *) priv;
+    uint32_t mask = 0x7fff;
+    uint32_t addr0 = 0x5555;
+    uint32_t addr1 = 0x2aaa;
+
+    if (dev->manufacturer == AMD) {
+        mask >>= 4;
+        addr0 >>= 4;
+        addr1 >>= 4;
+    }
 
     switch (dev->command_state) {
         case 0:
@@ -309,7 +348,7 @@ sst_write(uint32_t addr, uint8_t val, void *priv)
                 if (dev->id_mode)
                     dev->id_mode = 0;
                 dev->command_state = 0;
-            } else if (((addr & 0x7fff) == 0x5555) && (val == 0xaa))
+            } else if (((addr & mask) == addr0) && (val == 0xaa))
                 dev->command_state++;
             else {
                 if (!dev->is_39 && !dev->sdp && (dev->command_state == 0)) {
@@ -326,7 +365,7 @@ sst_write(uint32_t addr, uint8_t val, void *priv)
         case 1:
         case 4:
             /* 2nd and 5th Bus Write Cycle */
-            if (((addr & 0x7fff) == 0x2aaa) && (val == 0x55))
+            if (((addr & mask) == addr1) && (val == 0x55))
                 dev->command_state++;
             else
                 dev->command_state = 0;
@@ -337,7 +376,7 @@ sst_write(uint32_t addr, uint8_t val, void *priv)
             if ((dev->command_state == 5) && (val == SST_SECTOR_ERASE)) {
                 /* Sector erase - can be on any address. */
                 sst_new_command(dev, addr, val);
-            } else if ((addr & 0x7fff) == 0x5555)
+            } else if ((addr & mask) == addr0)
                 sst_new_command(dev, addr, val);
             else
                 dev->command_state = 0;
@@ -481,6 +520,8 @@ sst_init(const device_t *info)
     dev->id           = (info->local >> 8) & 0xff;
     dev->has_bbp      = (dev->manufacturer == WINBOND) && ((info->local & 0xff00) >= W29C020);
     dev->is_39        = (dev->manufacturer == SST) && ((info->local & 0xff00) >= SST39SF512);
+    if (dev->manufacturer == AMD)
+        dev->is_39    = 1;
 
     dev->size = info->local & 0xffff0000;
     if ((dev->size == 0x20000) && (strstr(machine_get_internal_name_ex(machine), "xi8088")) && !xi8088_bios_128kb())
@@ -941,3 +982,17 @@ const device_t sst_flash_49lf160_device = {
     .force_redraw  = NULL,
     .config        = NULL
 };
+
+const device_t amd_flash_29f020a_device = {
+    .name          = "AMD 29F020a Flash BIOS",
+    .internal_name = "amd_flash_29f020a",
+    .flags         = 0,
+    .local         = AMD | AMD29F020A | SIZE_2M,
+    .init          = sst_init,
+    .close         = sst_close,
+    .reset         = NULL,
+    { .available = NULL },
+    .speed_changed = NULL,
+    .force_redraw  = NULL,
+    .config        = NULL
+};
diff --git a/src/network/net_pcnet.c b/src/network/net_pcnet.c
index 02e3d32e7..9ddcfe29d 100644
--- a/src/network/net_pcnet.c
+++ b/src/network/net_pcnet.c
@@ -2896,7 +2896,7 @@ pcnet_init(const device_t *info)
     dev = malloc(sizeof(nic_t));
     memset(dev, 0x00, sizeof(nic_t));
     dev->name  = info->name;
-    dev->board = info->local;
+    dev->board = info->local & 0xff;
 
     dev->is_pci = !!(info->flags & DEVICE_PCI);
     dev->is_vlb = !!(info->flags & DEVICE_VLB);
@@ -2997,7 +2997,10 @@ pcnet_init(const device_t *info)
         pcnet_pci_regs[0x04]          = 3;
 
         /* Add device to the PCI bus, keep its slot number. */
-        pci_add_card(PCI_ADD_NORMAL, pcnet_pci_read, pcnet_pci_write, dev, &dev->pci_slot);
+        if (info->local & 0x0100)
+            pci_add_card(PCI_ADD_NETWORK, pcnet_pci_read, pcnet_pci_write, dev, &dev->pci_slot);
+        else
+            pci_add_card(PCI_ADD_NORMAL, pcnet_pci_read, pcnet_pci_write, dev, &dev->pci_slot);
     } else if (dev->board == DEV_AM79C961) {
         dev->dma_channel = -1;
 
@@ -3269,3 +3272,17 @@ const device_t pcnet_am79c973_device = {
     .force_redraw  = NULL,
     .config        = pcnet_pci_config
 };
+
+const device_t pcnet_am79c973_onboard_device = {
+    .name          = "AMD PCnet-FAST III",
+    .internal_name = "pcnetfast_onboard",
+    .flags         = DEVICE_PCI,
+    .local         = DEV_AM79C973 | 0x0100,
+    .init          = pcnet_init,
+    .close         = pcnet_close,
+    .reset         = NULL,
+    { .available = NULL },
+    .speed_changed = NULL,
+    .force_redraw  = NULL,
+    .config        = pcnet_pci_config
+};