Dear Yotsarun,
As you mentioned - you will use the Jarvis, so have the 'Jarvis' expected specs ready for you.
64GB RAM + 16 Cores CPU + 500GB Disk space.
Do keep in mind that future Portal 4.3 is expected to have the option of using an external/remote Jarvis - which might change those specs if you have one Portal and one Jarvis Server.
We do not have an ETA for this version yet - so I would suggest be ready with what we suggested here today.
Hope this helps,
Kind Regards,
Amit.