This is a new machine with Z490 Strix E motherboard with i9-10900K/64GB,
Intel® Ethernet Controller I225-V, Intel® Wi-Fi 6 AX201 160MHz

When I connect (to any data provider) on Ninjatrader (7 or 8/32 or 64 bit), my internet speed drops down to a crawl (600Mbps to less than 10). Once i disconnect, speeds are back up to its highs. NT support could not help. I checked all my drivers and they are all latest and greatest. Other platform connections (TOS when it works or tradestation work fine). Same happens on both wired or wireless connections.

Anyone have any thoughts?

Off the bat that sounds like a driver issue,

I'd ensure any bandwidth prioritisation software (which you might have installed with that motherboard) is correctly calibrated as if it sees NT as a high priority app it may be limiting bandwidth to prioritise latency.

A guess really but worth checking, also confirm overall usage of your bandwidth using task manager as this will rule out other apps actually using your bandwidth.

You are right. I think i found the culprit. It was one of those bandwidth prioritization software. It comes with the ASUS motherboard utilities package. It is called GameFirst IV. This damn thing was thinking Ninja was a game and slowing everything else down. I uninstalled it and the system appears to be working fine now. Thanks!

Excellent! Well my personal opinion would tell you to keep it but see if you can alter the settings as in my opinion when it works its fantastic. (even if not used for gaming)

Adz3000 

Excellent! Well my personal opinion would tell you to keep it but see if you can alter the settings as in my opinion when it works its fantastic. (even if not used for gaming)

I agree. I will install it again and try to configure it over this weekend. Thank you!