Help understanding and selecting cards, 7i76E/7I96/7i95?

Hello

I have been reading a bit on the different cards and I frankly need help understanding the differences between them.

I currently have an old Skyfire CNC mill that I plan to change over to mesa card control and Linuxcnc.
I have some sort of USB interfaced controller with mach 3 running on a PC at the moment.
This is controlled by Leadshine HBS57 hybrid servo drive controllers, they are clearly labelled with signal inputs etc. so I assume I can get them to work. I also have a VFD running a 24k rpm spindle, I assume that is no problem with either of these cards.
I do think I will need to change limit switches etc. so I am prepared for that.

I plan to exchange the PC to an old server pc with some proper ECC ram etc. for maximum stability and hopefully a small touch screeen to go with that.

For example, the 7i76E seem to be pretty common 5 axis capable card with lots of input/output, but it seems to be older then the others, are there any obvious disadvantages with it when compared to the other cards?

7i96 seem to be quite similar with 5 axis control and half the price with reduced IO options? If so, I would expect this card to be the most common card in use, but from what I can tell, its not. Am I missing something here?

7i95 seem to be quite similar to the 7i76 but 6 axis capable. If I understand this correctly 6 axis is useful if I would like to upgrade to 5 axis + toolchanger?

Im currently leaning towards getting the 7i95 for its 6 axis capability, but I want to make sure I did not miss anything.

My highly personal understanding is that the 7i76e has been around for some time and is very well suited for a stepper motor machine, it has analog spindle control and lots of inputs so is suitable for a small panel. But things have changed, the spindle is often controlled by some usb dongle, a touch screen and handheld usb-based mpg are often used, reducing the i/o need. The 7i96 is a response to that and cost less and is more attractive. It is relatively new so not so many out there yet. The 7i95 is a suited for the many servo-drives that use step/dir as control-method and has the corresponding encoder inputs. So if you know that you will need encoders for the axiss go for the 7i95. If your spindle controi is via usb go for the 7i96. You can always add encoder interface afterwards shoud you need it, I myself use 7i76e with a 7i85s and like that a lot. Today I might have bought the 7i96 fot my lathe with stepper motors and the 7i95 for the milling machine with stepper motors and linear scale feedback.

hi as you already got the parport settings
even a 7i92 at less then 100USD is good to go eth and hardware stepping

but a 7i96 is a best guess if you only want to upgrade
the 7i76e will boost you to a match higher level

I am interested in the 7i95, for the 6 axis and encoder interface this board supports. Its a shame they didn't add the spindle support like the 7i76e, What is the best way to wire spindle control to the 7i95 as the manual does not reference this at all. I would like an ATC spindle driven with VFD and encoder for ridged tapping etc.
Regards
Ian

Which board did you settle on for your Skyfire upgrade

I'm also very interested in the 7i95 as Ian said. Could someone explain to me how I can use an analog spindle on this board? For example, is it possible to communicate with a Delta inverter?

Ingo

The 7I95 has no analog spindle output, but you can and an external
PWM --> analog converter

Can you tell if it is a Mesa, which is the external PWM model -> analog converter?