BRIX i7-7557, unexpected guts.

Just got my BRIX i7-7557 delivered and I pulled it apart to just look inside as the listing said 256gb SSD. Well it has 2 SSDs, one mounted to the board and the other mounted to the back cover like normal. Both of them Samsung with the small board mounted one being 500gb and the cover mounted o e being 1TB and it’s an 850 EVO which shocked me. I only paid $110 for this computer and wasn’t expecting this much coin in SSDs to be inside. 

what do you recommend, pull one and just use the board  mounted SSD ok keep them both? Seams kinda over kill to use such a nice SSD for just LinuxCNC QRplasmaC.
Thank you for any advice you can provide on setting this up for optimal performance.

You lucky b....
Leave the small one in, yank the big one out.
Nice that i do not have to explain more as the physically small is also capacity small.
Reason for it being, the small one seems to be M-SATA only, so it will not work on some normal mainboards, while the big one works on anything with a normal SATA connector. Or you can buy an external case for the big one at usually 7-15$ (insist on finding a USB-C or USB 3.0) and use it for whatever you like, even installing LinuxCNC on it and testing any PC you come near to, since Linux boots from anything and on anything (well almost, for me 99% of the time)

I pulled the big SSD and installed QTpladmaC and disabled the normal bios stuff. Then ran a test with and without hyper threading on. You can tell which is which from the top left core count. Is one better than the other? Also no cores are isolated. These are at 500sec run times

Both should be perfectly fine even for software stepping to a certain extent.
Although it is strange you got worse base period latency with hyperthreading disabled ... (what is the HTML code for confused?)
Edit:
Forget the last line above, i was looking at the wrong numbers.

where you are not using a parallel port run:
for Mesa, the real test is the network latency.

Rod, repeat after me: Always use --show, it is disheartening seeing people here get happy looking at results and totally missing the striped columns on both sides of the graph.