Prima http://www.speedguide.net/analyzer.php mi dava come "Default Receive Window (RWIN)" 17000 e qualcosa...
Ora, seguendo la guida e facendo vari calcoli, l'ho settato a 32120.
TCP options string = 020405b401010402
MTU = 1500
MTU is fully optimized for broadband.
MSS = 1460
Maximum useful data in each packet = 1460, which equals MSS.

Default Receive Window (RWIN) = 32120
RWIN Scaling (RFC1323) = 0 bits
Unscaled Receive Window = 32120

RWIN is a multiple of MSS
Other values for RWIN that might work well with your current MTU/MSS:
513920 (MSS x 44 * scale factor of 8)
256960 (MSS x 44 * scale factor of 4)
128480 (MSS x 44 * scale factor of 2)
64240 (MSS x 44)
bandwidth * delay product (Note this is not a speed test):

Your RcvWindow limits you to: 1284.8 kbps (160.6 KBytes/s) @ 200ms
Your RcvWindow limits you to: 513.92 kbps (64.24 KBytes/s) @ 500ms
MTU Discovery (RFC1191) = ON
Time to live left = 55 hops

TTL value is ok.
Timestamps (RFC1323) = OFF
Selective Acknowledgements (RFC2018) = ON
IP type of service field (RFC1349) = 00000000
Ho riavviato, ho fatto vari tests e il risultato č sempre lo stesso!
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