Question Slow download speeds on high end PC (tried loads of fixes) ?

Jan 16, 2021
Hello all,

This is my first post so please be gentle!

To start here are my PC specs;
ROG Crosshair VIII Formula MOBO
AMD Ryzen 9 3950x CPU
G.Skill 64GB DDR4 3600 RAM
Gigabyte Aorus NVMe gen4 PCIe M.2 1TB SSD
ASUS ROG Strix GeForce RTX 2080 Ti OC Edition 11GB GDDR6
Windows 10 Home 64bit

Today I was downloading a piece of software to my main PC and my laptop and suddenly realised that my laptop was downloading it at about 41Mbps but my PC was downloading at around 5-6Mbps (task manager). I thought this was odd so downloaded them again and had the exact same results. I then tried from a another PC on my network and it again downloaded at around 40Mbps but my high end PC was stuck at 5-6Mbps.

I began investigating and thought it was maybe a bad ethernet cable, so tried a new one and was still the same. I then plugged my laptop into the exact same ethernet cable and got fast speeds so I ruled out any networking hardware straight away (my network is all unifi equipment). My PC has a ASUS mobo which has a 1g ethernet adapter, a 5g ethernet adapter and wi-fi 6 adapter. I have tried the same scenario on all three networking adapters and still get the same slow speeds even after updating all drivers and checking they are all set to forced gig duplexing.

I then tried all of the following steps with no improvement;

  1. I tried to download the same file via Microsoft edge instead of chrome with no difference.
  2. I have tried moving my downloads folder from my M.2 drive to the HDD drive in case of a software bottleneck there but again the same slow speeds.
  3. Updated the BIOS, all chipsets and windows - no difference
  4. I do not have ROG GameFirst installed
  5. I disabled all antivirus programs and closed all unnecessary background programs
  6. Ran a speed test using and get about 37Mbps download!
  7. Tried downloading files from another site and it got to about 17Mbps sometimes but this is still far from the 40Mbps my other devices are getting
  8. I have checked that no power saving options are turned on for the ethernet adapters or my system
  9. I have uninstalled tunnel bear VPN in case this was clashing somehow
I don't think I am missing anything obvious and I am all out of ideas so any help would be greatly appreciated before I decide to do a full windows reinstall

Image 1: Slow download speed problem PC
Image 2: C drive speeds on problem PC
Image 3: Much faster speeds same ethernet cable on Laptop
Image 4: This morning I tried a file transfer from my internal server to my M.2 drive and have decent speeds (816Mbps) so not a hardware or driver limitation surly?

Thanks in advanced
Last edited:
Jan 16, 2021
If you go to windows settings, network properties tab, can you post that info? What drive are you downloading to? I'm interested to see what speed the drive is working at during a download.
Thanks for the reply. I believe the following image shows what you are asking for. As for the drive, my downloads are currently going to my M.2 C drive but I have also tried changing this to my HDD to see fi there was a difference but unfortunately not.

Jan 16, 2021