VPN Going Slow on router


I have Installed Openwrt, X-wrt and pcwrt and I ran Wireguard, Openvpn on all of them.

when I set the VPN on the router, I will get slow speed than when i set vpn on android and ios and windows platforms.
my speed is 2mb/s , when I using from android , etc .. I will get 1.6mb/s , but on Router I have get 300kb/s to 600kb/s ... !!! all of settings are correct... all of network limiters are off...
CPU load in Router is very low under 1.

Someone know what is the problem exactly?

Your PC and smartphones almost certainly have encryption hardware accelerator.
And then the router only moves the encrypted data, which is just data.

If you run the VPN tunnel on the router the router CPU has to do the encryption and decryption.

Buy a router with bigger (faster) CPU to solve the problem. Or a VPN router which hopefully have cryptographic hardware accelerator.

Hi and Thanks for reply.

Are you Pretty sure with a powerful Router speed going Better?
Xiaomi 4c has 64Mb Memory and single core CPU.
But if we need more Resource such as CPU, why when I use maximum bandwidth cpu load on Xiaomi.4c will not load over 1 ?

Can you post a snapshot from top when you are downloading something through VPN?

Pretty sure. Cryptographic solutions are only about raw processing power since it is all about calculations and not that much memory.

I talk more like at least 1GB memory with dual core (or more) (as many GHz as you can find) CPU to run crypto solutions fast and have anything left for the router ordinary jobs.