very slow broadband upload speed on win 7 box

I have 2 w7pro boxes on a home workgroup gigabit lan running on Asus P8Z77 motherboards with Realtec PCIe GBE NIC's.  One box has an i7 2700 processor and one an i7 3770.  Both connect to a Vigor 2800 router through a Netgear gigabit smart switch. Both boxes use fixed ip addresses on a 192.168.3.x subnet.  Both have a similar collection of application programs.

As far as I can tell both NIC's are set up identically although the driver versions are different they both report that the best driver is installed.

Both boxes report broadband download speeds of around 11-12 Mb/s which is correct for my connection.  While the 2700 box uploads at 0.7 to 0.8Mb/s (again correct) the 3770 only manages between 0.01 and 0.02 Mb/s.

I have of course bypassed the switch and house cabling by connecting the box directly to the router, but it makes no difference.  There is nothing in the router or switch configs to indicate why the upload speed is so low.  Pings to from a cmd window are identical on both boxes at 37ms.

There is nothing that I can see to explain the poor upload speed on the 3770 box.  Can anyone give me some pointers where I should be looking next?

It seems clear that it is a box issue, but I can't find the problem.


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Skyler KincaidConnect With a Mentor Network/Systems EngineerCommented:
You should download the most recent drivers from the manufacturers website. The drivers on the disc or from Windows Update aren't always the newest driver.
Skyler KincaidNetwork/Systems EngineerCommented:
Have you tried rolling back the driver in the trouble machine? Sometimes the newest driver isn't always the best.

Also, what are you using to determine the upload speed?
chrisatworkAuthor Commented:
Both boxes are from new as supplied. One is about 10 months old, the other a few weeks.  Custom built, from the same source, so no roll back available.  The older machine is the i7 2700 that has no problems.  Could possibly install the older driver set to see if that is the issue as should have the nic cd's.  Haven't checked inside to see if the nic's are the same.

Using the same online speed checker site, running the checks one after the other with no other LAN traffic.  Have tried plugging the bad machine directly to the router, also crossplugging at the switch to check for faulty socket, makes no difference, so don't think it's the LAN traffic or the cabling.

chrisatworkAuthor Commented:
Ok  I replaced the driver with the latest one from the Realtek website - no change.  I replaced the driver with the one that gives the correct upload speed on the i7 2700 machine - no change.  I ran the Realtek diagnostic tool and it reported all ok.

Something is slowing down the tx side of the card.

Tomorrow I will do some file transfer checks to see whether tx rate over a local lan is also slow (too late now).  If not then I am completely stumped.

Also ran a complete virus scan which found nothing.
chrisatworkAuthor Commented:
Ok I found the solution, not directly from the posting by xKincaidx but from research prompted by the post - the lovely builders had enabled the Asus Network iControl for some inexplicable reason, knowing I hate unnecessary software, and that killed the upload speed.  Turning it off restored the speed instantly.

Just by chance I found a comment in a forum and gave it a try.  Well worth making a note somewhere about this for others to read
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