<If someone has tips for me to use with that laptop, I'm all ears so to speak.>

A door stopper maybe.

Seriously though, rendering with an old laptop shouldn't make any difference, maybe just take longer. Check all your settings in BiaB and your buffers. Sound card shouldn't have any effect because you are still in the digital realm, but check your drivers anyway. Maybe try MME instead of asio. You mentioned a usb stick, maybe it is the usb socket. Try transfering a file via e-mail or cd. Could be millions of things. If the laptop is slow as well as old you could try using it as an internet pc to keep your music pc clean without all the antivirus stuff.

Chris