speed up my LAN

I have 2 computers in my LAN. They are connected through 2 identical 100
NICs. To all appearances, they should be communicating that fast, but The
best I can get is ftp'ing at 600 KB/s. What more can I do?

On Computer C, I did
mii-tool -l -w eth0
mii-tool -r eth0
and saw the following log entries:
Sep 25 01:00:23 localhost kernel: eth0: Link changed: 10Mbps ,half duplex.
Sep 25 01:00:23 localhost mii-tool: eth0: no link
Sep 25 01:00:25 localhost kernel: eth0: Link changed: 10Mbps ,half duplex.
Sep 25 01:00:26 localhost mii-tool: eth0: negotiated 100baseTx-FD, link ok

It looks like the kernel is setting the media yet the below mii-tool
commands from both computers show the network cards are set to 100.
Can the kernel set the media limit to 10Mbps, regardless of what the NIC
is set to?

Computer D's log file from similar commands shows:
Sep 25 01:09:01 dave kernel: eth1: Link changed:
Sep 25 01:09:02 dave mii-tool: eth1: no link
Sep 25 01:09:03 dave kernel: eth1: Link changed: 100Mbps, full duplex
Sep 25 01:09:04 dave mii-tool: eth1: negotiated 100baseTx-FD, link ok

Computer C is running 2.4.18. If you want, I can include the net part of
the kernel config file.


My systems look like this:

Computer C---eth0------------eth1---Computer D---eth0-------Internet
RH7.3 (DFE-530TXS) (DFE-530TXS) RHF4
sundance sundance

Info on Computer C:
C has a second NIC, eth1, thats not connected to anything and
shouldn't be an issue.
C's iptables is only the bare minimum,4 lines and accepting everything
from the LAN is on the second line.

===module.conf===
alias eth1 ne2k-pci
alias eth0 sundance
#options sundance media=100mbps_fd
#Commented out as forced media option made no difference.

===ifconfig===
eth0 Link encap:Ethernet HWaddr 00:05:5D:FE:0A:48
inet addr:192.168.1.2 Bcast:192.168.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2721914 errors:0 dropped:29 overruns:0 frame:0
TX packets:4483367 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:488559695 (465.9 Mb) TX bytes:1551477395 (1479.6 Mb)
Interrupt:9 Base address:0x4c00

eth1 Link encap:Ethernet HWaddr 00:50:BAD:4D:EF
inet addr:192.168.2.1 Bcast:192.168.2.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:4 dropped:0 overruns:0 carrier:8
collisions:68 txqueuelen:100
RX bytes:0 (0.0 b) TX bytes:240 (240.0 b)
Interrupt:11 Base address:0xfc60

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:180 errors:0 dropped:0 overruns:0 frame:0
TX packets:180 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:17051 (16.6 Kb) TX bytes:17051 (16.6 Kb)

===mii-tool -v -v===
eth0: negotiated 100baseTx-FD, link ok
registers for MII PHY 0:
1000 782d 0022 1630 0101 45e1 0007 2001
1000 782d 0022 1630 0101 45e1 0007 2001
1000 782d 0022 1630 0101 45e1 0007 2001
0000 0000 0000 0000 0000 0000 0000 0000
product info: vendor 00:08:85, model 35 rev 0
basic mode: autonegotiation enabled
basic status: autonegotiation complete, link ok
capabilities: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD
advertising: 100baseTx-FD
link partner: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD flow-control
SIOCGMIIPHY on 'eth1' failed: Operation not supported

===modprobe.conf===
alias eth1 sundance
alias eth0 3c59x
options 3c59x vortex_debug=0
options 3c59x enable_wol=1

===ifconfig===
eth0 Link encap:Ethernet HWaddr 00:01:02:3F4:19
inet addr:68.148.xxx.xxx Bcast:255.255.255.255 Mask:255.255.254.0
# I xxx'ed the above address now
inet6 addr: fe80::201:2ff:fe3f:d419/64 Scope:Link UP BROADCAST
RUNNING MULTICAST MTU:1500 Metric:1 RX packets:100547 errors:0
dropped:0 overruns:0 frame:0 TX packets:15763 errors:0 dropped:0
overruns:0 carrier:0 collisions:739 txqueuelen:1000
RX bytes:28644124 (27.3 MiB) TX bytes:1985625 (1.8 MiB)
Interrupt:11 Base address:0xc000

eth1 Link encap:Ethernet HWaddr 00:05:5D:FE:31:F1
inet addr:192.168.1.1 Bcast:192.168.255.255 Mask:255.255.0.0
inet6 addr: fe80::205:5dff:fefe:31f1/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:4393731 errors:0 dropped:0 overruns:0 frame:0
TX packets:2531609 errors:1 dropped:30 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1764702018 (1.6 GiB) TX bytes:168932780 (161.1 MiB)
Interrupt:5 Base address:0xc800

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:10427 errors:0 dropped:0 overruns:0 frame:0
TX packets:10427 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:2541896 (2.4 MiB) TX bytes:2541896 (2.4 MiB)

===mii-tool -v -v===
eth0: no autonegotiation, 10baseT-HD, link ok
registers for MII PHY 24:
1100 182d 0000 0000 0061 0020 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
product info: vendor 00:00:00, model 0 rev 0
basic mode: autonegotiation enabled
basic status: autonegotiation complete, link ok
capabilities: 10baseT-FD 10baseT-HD
advertising: 10baseT-FD 10baseT-HD
link partner: 10baseT-HD
eth1: negotiated 100baseTx-FD, link ok
registers for MII PHY 1:
1000 782d 0022 1630 05e1 4101 0007 2001
1000 782d 0022 1630 05e1 4101 0007 2001
1000 782d 0022 1630 05e1 4101 0007 2001
0000 0000 0000 0000 0000 0000 0000 0000
product info: vendor 00:08:85, model 35 rev 0
basic mode: autonegotiation enabled
basic status: autonegotiation complete, link ok
capabilities: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD
advertising: 100baseTx-FD 100baseTx-HD 10baseT-FD 10baseT-HD flow-control
link partner: 100baseTx-FD