What OS upgrade are you taking?
A full new build? e.g. RHEL5 or 6 to RHEL7 ?
Or a point release? e.g. RHEL6.4 to RHEL6.8 ?
A full build, is not really an upgrade, there's no upgrade path to change major versions of RHEL. So you'll be rebuilding the AMD server from scratch. Check the nCipher documentation (very important), you'll probably have to backup the 'security world' data, so you can reuse the card without re-initialising it (losing the certs) on the new install.
Point release updates can be done in place, with 'yum update' (assuming an internet connection/connection to a satellite server). And cause no issues for the nCipher card.