Real life speeds with Wi-Fi 3x3 AC standard

Hi,

​

I have Segamcom 5655 RF modem from my ISP which supports up to 1300 Mb/s on 5 GHz Wi-Fi, and my HP ProBook 4540s has a BCM94352HMB Wi-Fi card which supports up to 867 Mb/s speeds with 2x2.

https://i.ibb.co/23wrs7g/Screenshot-2019-04-15-at-10-16-13.png

​

I get around 570 Mb/s down and 580 Mb/s up on Wi-Fi.

​

I have 1 Gb/s fiber at home.

​

The question is, if I replace the Wi-Fi card with a 3x3 Wi-Fi, what will be the real life speeds ?