Comcast upgraded my gold service from 3300/384 to 6600/768.  Thats exactly twice as fast as before, right? ... WRONG!  The only thing that increased is my upload speed, SLIGHTLY!  I can see absolutely no increase in my download speed.  I contacted Comcast and they told me to recycle my modem and all would be good.  Did that 150 times and no increase.  Here are the required postings:

1. Windows XP Service Pack 2
2. Comcast Gold 6600/768
3. Cablenut 4.08
4. Results of Tweak Test:   http://ttester.broadbandreports.com/tweak/block:2ed637e?service=cable&speed=6600&os=winXP&via=normal
5. Testmy speed test results: 
::::::::::.. Download Stats ..::::::::::
Connection is:: 3991 Kbps about 4 Mbps (tested with 2992 KB)
Download Speed is:: 487 kB/s
Tested From:: http://www.testmy.net/
Test Time:: Sun Jan 30 08:35:41 EST 2005
Bottom Line:: 71X faster than 56K 1MB download in 2.1 sec
Validation Link:: http://testmy.net/id-BD1P4LGMX

::::::::::.. Upload Stats ..::::::::::
Connection is:: 400 Kbps about 0.4 Mbps (tested with 579 KB)
Upload Speed is:: 49 kB/s
Tested From:: http://www.testmy.net/
Test Time:: Sun Jan 30 08:37:35 EST 2005
Bottom Line:: 7X faster than 56K 1MB upload in 20.9 sec
Validation Link:: http://testmy.net/id-9RLAU02JZ

Nitro results:  TCP/Web100 Network Diagnostic Tool v5.2.1e
click START to begin
Checking for Middleboxes . . . . . . . . . . . . . . . . . .  Done
running 10s outbound test (client to server) . . . . . 490.00kB/s
running 10s inbound test (server to client) . . . . . . 3.88Mb/s
Your PC is connected to a Cable/DSL modem

Tracert Results:  Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

C:\Documents and Settings\Owner>tracert testmy.net

Tracing route to testmy.net [67.19.36.6]
over a maximum of 30 hops:

  1     *        *        *     Request timed out.
  2    14 ms    10 ms    11 ms  68.87.59.149
  3    14 ms    10 ms    25 ms  srp-8-1-ar01.owingsmill.md.md02.Comcast.net [68.
87.59.225]
  4    22 ms    12 ms    12 ms  pos-7-1-cr01.whitemarsh.md.core.Comcast.net [68.
87.19.173]
  5    27 ms    16 ms    20 ms  12.118.102.9
  6    20 ms    21 ms    16 ms  tbr2-p032501.n54ny.ip.att.net [12.123.3.86]
  7    23 ms    20 ms    24 ms  tbr2-cl1.wswdc.ip.att.net [12.122.10.54]
  8    37 ms    47 ms    35 ms  tbr1-cl1.attga.ip.att.net [12.122.10.70]
  9    38 ms    38 ms    34 ms  tbr2-p012501.attga.ip.att.net [12.122.9.158]
 10    49 ms    54 ms    52 ms  tbr1-cl1.dlstx.ip.att.net [12.122.2.89]
 11    53 ms    56 ms    55 ms  gar1-p360.dlrtx.ip.att.net [12.123.196.101]
 12    54 ms    54 ms    53 ms  12.119.136.14
 13   143 ms   205 ms   207 ms  dist-vlan31.dsr3-2.dllstx3.theplanet.com [70.85.
127.30]
 14    51 ms    53 ms    49 ms  dist-vlan22.dsr1-2.dllstx2.theplanet.com [70.85.
127.76]
 15    56 ms    56 ms    55 ms  dsr2-1-v2.dllstx4.theplanet.com [12.96.160.39]
 16    50 ms    53 ms    53 ms  gig1-0-2.tp-car9-2.dllstx4.theplanet.com [67.18.
116.86]
 17    51 ms    59 ms    52 ms  6.67-19-36.reverse.theplanet.com [67.19.36.6]

Trace complete.

Use Linksys BEFW11S4 Router, with two wired, and one wireless computer.
NIC set to 10 half duplex
Sygate Firewall Installed
Ran Spybot, Adaware SE, and Crap Cleaner.  Computer free of viruses and/or spyware.
Used one of your cablenut settings

Comcast says that everything is okay on their end.  Please help.
Thank you very much,    Chris.