Mesa cards vs. jitter + latency?

I need another pc for linux cnc and I'm wondering if using a mesa card eliminates the headache of finding a pc that runs with low jitter.
As far as I understand using a mesa card will offload the step generation (I use steppers) to the card. On the other hand things still happen in realtime in software in linuxcnc so the real time capabilities of the pc might still be concern?

The question is if I still need to care about the pc hardware dependent jitter and latency if I use a Mesa card or if can I use an arbitrary pc?
I have enough decommissioned hardware available and I consider the cost of a mesa card a non-issue if it enables me to just pick any motherboard + cpu + vga without headaches about jitter, latency and whatnot.

Second question would be laptops: Are there meanwhile solutions that allow using a regular laptop with an external mesa card? The mesa store lists so much linuxcnc compatible cards that it is difficult to keep track of what is actually possible.

Thank you guys in advance...!

Using hardware step generation does not remove latency considerations from choosing a PC. It just lowers the bar a bit (40-100K ns is probably good enough vs 10-20K when your trying to software step).

I still don't think most laptops are good enough, and they would be difficult to integrate, and most aren't built to withstand a machine tool environment. Also turning off all the power saving features (assuming it can even be done) to get adequate latency, can potentially damage a laptop (cause them to over heat ...)