I just made some new brass gibs for my X2 and for the first time ever attempted to go higher rate than I've been on table movement in the past.

I was surprised to see the flag come up that say's velocity requested exceeds blah blah blah limits of configuration.

I know they're are others that are moving at a faster rate than this at 45k Hz and I understand that leadscrew tpi has a lot to do with that.

But does it understand my max feedrate is based upon "steps per" or something?

Where's the bottleneck if it's not in the leadscrew?

Am I missing another setting somewhere?

Don't get me wrong, I'm very happy with the new feedrates, just taken aback that the system is infringing on faster movement.

But does it understand my max feedrate is based upon "steps per" or something?

That is exactly what the max velocity is determined by, assuming your motors are physically capable of course.

45KHz means that you can output a max of 45,000 steps per second.
Say for example your steps per unit were 4,500 then that would mean that  you could  get a velocity of 10units per second (45.000/4,500), so velocity would be 600 units per minute. (10 units x 60 seconds)
Now if your steps per unit were 9,000 then that would mean you could get a max of 5units per second or 300 units per minute.
Hood

Just to add a wee bit more. Your title says maxed out at 84 IPM.
That would suggest you have a step per unit of approx 32,142.
45,000/ 32,142 = 1.4 units  per second or 84 units per minute

Hood