I am currently on 2019.6 version on an aging i7-4790. I will be upgrading to a ryzen 7 3800x soon. My question is, do I need to remove and recompile gromacs after upgrading? If possible, I would like to keep my installation to avoid possible variation in experimental runs. I did try googling for answer to no avail.
GROMACS modification: No
No, you’ll be fine with the previous installation (because the default SIMD instruction for the i7-4790 is supported on the Ryzen CPU as well, that is the GMX_SIMD option will be configured to have the AVX2_256 setting).
Thank you so much!
One following question, on the other hand, is there any missing features that I would miss out because it was originally compiled for a i7 4790?
If you built GROMACS with the default flags, you will not.
That said, you would probably benefit greatly from recompiling using a recent gcc version, e.g. 9 or 10 if you are after the best performance on your workstation.