I signed up for Nat West student account last week, but when I sent off my student loan forms months back I gave my HSBC Bank details.
I still haven't heard from then with regards to how much loan I am getting etc..
Should I ring them up and give them my new details?
Yep - ring or email then confirm in writing I think. When I informed the SLC of my bank details, I emailed them first then sent them a letter to confirm the change.
You can still get your loan paid into your HSBC account (which is what im doing), but if you want it in your Natwest one, when you get your final confirmation they send you a change of bank form.