Precision T7600 Win10Pro dual GB nics uploading at 1gbps but downloading at 300mbps max

Question

IT Pro with 11 years experience, stumped by a client with 3x t7600s who can upload locally at gbps speeds but cannot download at anything over 300mbps speeds.

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Tried adding a expansion intel nic to pci-e slot without improvement!

latest bios

confirmed all power save settings in windows and on nic driver off

confirmed drivers

clean install of windows on latest update

no av

nic showing gb connection

tried direct connection to another pc with cross over and manual ips with network share and confirmed sure enough, can pull a file FROM a t7600 precision dell on SSD via SMB at 90-105 megabytes per second, but pushing data to the t7600 or pulling data on another system to the t7600 dell results in 30 megabytes per second.

Different cables

cross tested with laptop and laptop is full 1gbps up / 1gbps down under same scenario as t7600

confirmed metered mode is off

tried every setting in the bios for hours rebooting and cross testing without improvement

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So this is a head scratcher because at first we only had 3x t7600 at 300mbps speeds, then we learned its only down speeds, and up speeds are actually full 1gbps!

What's worse? There's NOTHING on google... how often do you come across something where you cannot find any information on the issue?! Best I found was a OptiPlex with similar issues cross tested by Linux to discover it was a power settings in the bios of the OptiPlex that fixed the issue.

Tried the following in admin cmd prompt

ipconfig /flushdns
nbtstat -R
nbtstat -RR
netsh int reset all
netsh int ipv4 reset
netsh int ipv6 reset
netsh winsock reset

and trying linux to validate its not hardware and is infact windows on this particular model of dell/nic.

I used the latest Ubuntu release as a boot disk and can confirm it functions at 100% FULL gigabit speeds up AND down.

In Windows 10 x64, our DOWN speed is limited to 300mbps and UP speed is full 1000mbps Gigabit speeds.

Please make suggestions on what to evaluate in the IP STACK in windows 10 and ways to evaluate the wait chain in the system process with handling the data.

Answer 1

The vendor Dell will be your best resource to troubleshoot the problematic hardware.

--please don't forget to Accept as answer if the reply is helpful--

Answer 2

Hi,

Thanks for posting in Q&A platform.

It seems your issue is that uploading slow performance issue. Regarding of uploading slow performance issue, it's necessary to analyze performance log and network traffic to find the cause. However, analysis of log is beyond our forum support level and due to forum security policy, we have no such channel to collect user log information. So, we recommend you open a case with MS Professional tech support service, they will help you open a phone or email case to Microsoft, so that you would get a technical support on a one-to-one basis while ensuring private information.

Here is the link, you could find phone number of your region accordingly from the link below::

https://support.microsoft.com/en-us/gp/customer-service-phone-numbers

Best Regards,
Sunny

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Answer 3

Any progress or updates?

--please don't forget to Accept as answer if the reply is helpful--