VPN's will always throttle download speeds

Nowucme

I have tried 5 different VPN services over the past 4 years. I currently have 500u download speed. With Express VPN enabled my speed drops to a fraction of that like a dismal 45u to perhaps 90u tops. This is largely due to the Tap adapters V9 that VPN suppliers install their adapters are only rated for 100mbps my Windows 10 Realtek ethernet adapter is capable of handling 1Gbps and with VPN disabled I can easily get speeds over 500u.VPN software suppliers use a max of 100u on their tap adapters simply because to increase the speed of the tap adapter would overcome most of the servers they tunnel your internet traffic thru. And they further throttle your speed at peak periods to enable traffic from more users. No matter what performance claims VPN suppliers make ....and they have too many to list you will never get free of the throttling.I recently installed a free app called "Belarc Advisor" it shows all the PC  processes,installed software,hardware, etc. etc. devices and ethernet adapters including those adapters installed by VPN software it will be an eye opener if you choose to download it and install it.I'm unable to paste my results of Belarc to this page.

Max-P

The TAP adapter doesn't run at 100M. This value is only provided to Windows for show in the UI, it is not used anywhere. I have a custom built version that says it runs at 10G and it changed nothing.

It is a known issue but it doesn't have anything to do with not overloading the servers (if we wanted to do that, we could throttle it at the server-side). Back when we started, very few people had access to speeds high enough to even exhibit this bug and it went mostly unnoticed for years.

The cause of the limitation is still not quite known, and it is fairly hard to fix. In the meantime, using a Linux or Mac computer or a pfSense router is the best way to get every bit of bandwidth you can get.

MeFirst

Too much encryption and not enough CPU?

Max-P

Nope. It's not the encryption, it's a limitation of the way the TAP driver is written for Windows and the constant switching back and forth between OpenVPN and the driver. Right now it passes individual packets at once as far as I can tell, and at high speeds, the overhead of the context switches becomes significant enough that it limits the total throughput possible.