I’m having some of the strangest issues with my workstations.  Here are the specs:

ASUS Rampage V Extreme
Intel Core i7 5820K @ 3.30GHz
Corsair Dominator Platinum 64 GB
Samsung EVO NVMe 500GB solid state drive
Seasonic 1000W PSU

I recently upgraded to gigabit Internet with Spectrum Business.  I initially was seeing horrible speeds, anywhere from 100 Mbps to 300 Mbps.  I finally hooked my 15″ Mid 2015 MacBook Pro up with Lightning to Ethernet adapter and plugged directly into the modem.  I can see my connection is NOT the problem.  I see anywhere from 800 Mbps to 1.3 Gbps on the MacBook, CONSISTENTLY.  This is the mind-boggling part.

Now we go back to my Windows 10 Pro 64-Bit workstation.  I was on 1803 and updated to 1809 last night.

I consistently see speeds being gimped from the gigabit I should be getting to around 100-300 Mbps which is pissing me off.  I know that something is using up my network resources and or is doing some traffic shaping.  I’ve tried a clean boot, but some programs don’t adhere to a clean boot and keep running anyway.  I wish I could do a clean install but don’t have that kind of time anymore.  I may look into installing Windows onto one of the various spare PCs I have lying around the house but, procrastination and stuff.

In the meantime, I’d like to put this out there and if anyone else has seen their speed test speeds being gimped but clearly know that it’s working properly because they hooked up another device, whether it’s a Mac or another PC with a different OS or a clean install with no other applications running, let me know.

Something is gimping the connection.  I have disabled the firewall, antivirus, and any other programs that I can think of that would use the WAN link heavily.  I sometimes can see gigabit speeds through fast.com and speedtest.net, but it’s not consistent.  I know some people might be thinking well, there are peak hours and other various explanations, but that does not explain why my MacBook Pro can consistently, and I mean at any time of the day, do speed tests out to fast.com and speedtest.net’s various servers and see close to if not gigabit speeds!

I found a blog that suggested running TCP Optimizer from https://www.speedguide.net/downloads.php.  I ran it, and so far I see consistent gigabit speeds.  I will continue testing throughout the day and will report back if it’s a permanent thing.

Edit: 12/16/2018:

Well, I can confirm that the TCP Optimizer has fixed my issues.  If you see weird slowdowns on your WAN connection as though something is throttling your speed, check out the TCP Optimizer.  I ran it, changed the settings to optimal and restarted.  It’s been about a full 24 hours and no problems to report.  I’m seeing the full 1 Gbps connection being used on all speed tests.