Intel Pro/1000 & iperf

Наконец-то дошли руки протестить линк между серверами:
1. Сервер А: мать на se7501, 2*Xeon, Intel Pro/1000 MT Server adapter (установлен в PCI-X/133)
2. Сервер Б: мать на i915, 1*P4HT, Intel Pro/1000 MT Desktop adapter (установлен в PCI-E/x16)
3. Прямой "фирменный" патч-корд 5е напрямую в сетевые.

Постановка эксперимента:
А: iperf -s
Б: iperf -c А -i 1 -t 8 -d

Результаты:
------------------------------------------------------------
Server listening on TCP port 5001
TCP window size: 85.3 KByte (default)
------------------------------------------------------------
------------------------------------------------------------
Client connecting to А, TCP port 5001
TCP window size: 64.0 KByte (default)
------------------------------------------------------------
[ 4] local Б port 57790 connected with А port 5001
[ 5] local Б port 5001 connected with А port 48439
[ ID] Interval Transfer Bandwidth
[ 5] 0.0- 1.0 sec 6.65 MBytes 55.8 Mbits/sec
[ 4] 0.0- 1.0 sec 103 MBytes 865 Mbits/sec
[ 4] 1.0- 2.0 sec 107 MBytes 896 Mbits/sec
[ 5] 1.0- 2.0 sec 18.8 MBytes 158 Mbits/sec
[ 5] 2.0- 3.0 sec 6.37 MBytes 53.4 Mbits/sec
[ 4] 2.0- 3.0 sec 109 MBytes 913 Mbits/sec
[ 5] 3.0- 4.0 sec 6.45 MBytes 54.1 Mbits/sec
[ 4] 3.0- 4.0 sec 112 MBytes 940 Mbits/sec
[ 4] 4.0- 5.0 sec 110 MBytes 927 Mbits/sec
[ 5] 4.0- 5.0 sec 5.26 MBytes 44.1 Mbits/sec
[ 4] 5.0- 6.0 sec 110 MBytes 922 Mbits/sec
[ 5] 5.0- 6.0 sec 9.85 MBytes 82.6 Mbits/sec
[ 4] 6.0- 7.0 sec 109 MBytes 916 Mbits/sec
[ 5] 6.0- 7.0 sec 10.9 MBytes 91.2 Mbits/sec
[ 4] 7.0- 8.0 sec 111 MBytes 934 Mbits/sec
[ 5] 7.0- 8.0 sec 2.19 MBytes 18.3 Mbits/sec
[ 4] 0.0- 8.1 sec 872 MBytes 908 Mbits/sec
[ 5] 0.0- 8.1 sec 67.3 MBytes 70.0 Mbits/sec

Судорожно чешу репу и думаю, что же крутить.