Hello fellow C1 owner
I'm not anything to do with Corsair but on another thread I believe an employee states the following SF600 PSU will physically fit:
https://www.amazon.co.uk/Corsair-SF600-Fully-Modular-Supply/dp/B01CR1XGTG/
(edit) original thread here:
http://forum.corsair.com/v3/showthread.php?t=170300&highlight=corsair+1080ti
I see someone else states they got the SF750 to fit in the i160 which outwardly at least is a near identical chassis?
http://forum.corsair.com/v3/showthread.php?t=186466&highlight=SF600&page=2
I believe the statement on the 1080ti is going to be that you need a custom bracket to hold the cooling block on (again, I'd have to search on the forum a lot to see where it was I saw this).
(edit) See a discussion thread here for the not so great news, but: "The 1080ti in the one is a modified version of MSI DUKE card with our HG10 bracket attached to it."
http://forum.corsair.com/v3/showthread.php?t=180507&highlight=corsair+1080ti+bracket
Not directly about your query, but everything else I noted about the Corsair One from the forum:
Lots of successes with an improved 140mm fan in the top it seems. No major changes to lighting possible due to lack of space for a lighting controller. (edit) some discussion here:
http://forum.corsair.com/v3/showthread.php?t=170300&highlight=corsair+1080ti
Crashes/graphics cards issues: double check the PCIE cable or change it. (edit) some discussion here:
http://forum.corsair.com/v3/showthread.php?t=179875&highlight=corsair+1080ti
Motherboards: someone said the ASRock Z390 Phantom Gaming Mini-ITX motherboard fits (in an i160 version...), but note that Corsair say the X299 absolutely wont as they had to modify a daughter-board in order to get it to fit for the stock version in the later models.
(edit) http://forum.corsair.com/v3/showthread.php?t=186466&highlight=Upgrade
(edit) dont use the corsair PCIE cable with the Z390 boards though, reason on page two of this thread:
http://forum.corsair.com/v3/showthread.php?t=187028&highlight=corsair+z390&page=2
Original MSI board is still vulnerable to one of the Intel security issues as there's no bios update
http://forum.corsair.com/v3/showthread.php?t=187500
At least one Corsair One owner (Bocefuss4500) has gone the Ryzen route via a Asus ROG Strix X470-I Gaming and lots of other cool bits :)
http://forum.corsair.com/v3/showthread.php?t=187102
I9 upgrade thread:
https://forum.corsair.com/v3/showthread.php?t=183339
Did I miss anything about the corsair one? :) would genuinely like to know if there are any other tweaks not mentioned above
Hope this helps