Thank you for contacting Intel.
I understand you have tried different driver versions to no avail. You may try to configure the adapter's advance settings.
Turn off or disable the following:
1. Performance options - Adaptive inter-frame spacing
2. Performance options - Interrupt moderation rate
3. ALL TCP/IP offloading options
See if there is improvement with your network connection. If no improvement, try below:
1. Increase the Transmit Descriptors buffer size.
2. Increase the Receive Descriptors buffer size.
Hope this helps.
Thanks for the quick reply.
I tried the settings you suggested but nothing changed. The problem appeared around the time the 1511 Windows 10 update was installed. So I'm mostly suspecting this is an OS generated problem maybe in combination with my nic's drivers. I might be able to test my pc with an INTEL PRO/1000CT PCI-E adapter later this week and see how it goes. Any further suggestions are welcome, although I'm keeping my hopes down for a solution as my problem doesn't seem to be a common one.
Since this is an integrated network card, you may try to check -
1. if there are any BIOS, driver updates for your board model. Especially that you just updated to Windows* 10.
2. uninstall and reinstall your network card's driver - try using driver/software provided by Asus*
3. Try reinstalling Windows* 10, if you can.
In normal circumstances, increasing the transmit buffers should fix slow upload speed that you are experiencing.
Just a quick update. Tried an UBUNTU live cd today and network upload speeds were fast and normal as intended. So I'm definitely narrowing the problem down to Windows 10 not working with my onboard NIC especially after the latest build update. I will post an update when I have the new network card in my hands. I was really hoping for a solution either from Microsoft or Intel cause I really want to avoid reinstalling Windows 10 at the moment.
I was finally able to resolve my slow upload network speed problem. It seems that a network prioritization program (ASUS Network iControl) bundled with my motherboard somehow started causing the problem maybe in conjunction with the latest Windows 10 build update I mentioned above. The funny thing is I tried to completely uninstall it, because I never use it anyway, and this broke my networking altogether. Only after the successful reinstallation of the ASUS Network iControl program (I had a couple of unsuccessful attempts too!!!) was my networking up and running again and the slow upload problem magically disappeared at last. Of course now I'm stuck with this program which caused me the problem in the first place, I don't use it, but can't uninstall it either. Thanks a lot for your time and effort to help me resolve this issue.