[goveng]

I want to run a RAM upgrade in my machine. I know the 4,8 and 16MB expansions works on a 1400-5C CPU board but not 1400-5A.

Does anyone know what the differences are between these 2 revisions? Anyone had their 5A board upgraded to 5C?

[Tedger]

I have a 1400-5A with 4MB expansion. I never heard that the memory wouldn't work with the different revision letters. As long as it's a 1400-5, you should be good to go.
Here's a compatibility chart; https://www.fadalcnc.com/media/pdf/A...patibility.pdf

[goveng]

I have a 1400-5A with 4MB expansion. I never heard that the memory wouldn't work with the different revision letters.

ITS are saying..."Also if you have a 1400-5A and want to use 4,8, or 16 meg memory then you need to upgade it to a -5C. We can do that for $95.00"

https://itscnc.com/pcb-0030-p-165.ht...3565ba5bb66196

[Tedger]

Well,I looked it up and you are correct. You can only use PCB-0041(384K) on the 5A .

For the price people are charging for additional memory expansion. I would much rather purchase a calmotion.

[goveng]

The difference between 1400-5A and 1400-5C revisions is the crystal speed at U11.

1400-5A = 50 mhz
1400-5C = 48 mhz

On a 1400-5A change the crystal to 48 mhz and 4, 8 and 16MB RAM upgrades will work.