PCIE to PCI Adapters

That's the kernel that a standard install already has.

To be honest I'd re enable multi core, and test with that. Leave Hyperthreading disabled.
If the results aren't that great you can add isolcpus=2,3 (assuming 4 core)
isolcpus=1 (assuming dual core)

This link explains the editing kernel command line with grub
documentation.suse.com/smart/systems-man...parameter/index.html
And here
documentation.suse.com/smart/systems-man...parameter/index.html

RTAI kernel can be found here:
www.linuxcnc.org/dists/bookworm/base/binary-amd64/

RTAI Packages cane be found here:
www.linuxcnc.org/dists/bookworm/2.9-rt/binary-amd64/

Whereabouts in Oz is ya ?

Cheers I'll give it a go, (Its a first gen I5 so dual core)

I'm in SA

Multicore on with ISOLCPU=1 did the trick I think we are all sweet now.

Base thread max jitter with 5 GLXgears was 7300 when I opened a youtube video and let it play for a bit it only got up to 12200
I think.... I HOPE that is good enough for my little milling machine. Thanks again for all your help guys