Trev, "tower" to me means a desktop computer, but I suspect you might refer to a bank of hard drives? Could you clarify please?

In general, very few files need to be on your boot drive. There are 7 or so fonts, very tiny, and maybe a few other small things. Everything else in BIAB can reside on and run from another drive, including the USB drive PG Music ships some versions on, or your own external drive. I don't know if it would work on a networked drive, which might be what you are considering. If that's the case, it might take a call to PG Music Support to determine.

EDIT: John already covered this. He correctly added virtual instruments and effects. In my case, I did the 'minimal' install and I have the RealTracks and RealDrums on a separate hard drive. Works great and doesn't fill my SSD boot drive. Actually, I went one step further and put the system files (everything else) on a separate SSD drive. It flies.

BIAB 2024 Win Audiophile. Software: Studio One 6.5 Pro, Swam horns, Acoustica-7, Notion 6; Win 11 Home. Hardware: Intel i9, 32 Gb; Roland Integra-7, Presonus Studio 192, Presonus Faderport 8, Royer 121, Adam Sub8 & Neumann 120 monitors