dma and compatibility is hard to explain as varies alot between PCs. unless you have the cash i would not look for stuff that supports 4k 240hrz. also the second pc has to be powerful enough aswell. if the 2nd pc is to weak you will have lag and the aimbot will usually have some delay. the difference between 35t and 100t is quite big, it does not effect compatibility but 100t has better performance and such
i do not use captain dma but have heard some bad things about them. it is probably more safe to buy a new motherboard with a second slot so you can use the new stuff.
do not purchase from resellers as they just sell alibaba stuff from china anyways, it is much cheaper to buy from alibaba yourself.
you only need card and fuser aswell as the optional stuff for aimbot in terms of hardware. you can find many free guides online for how to set it up so dont pay some reseller for help.