It does have a reputation for having "rahs" and being public school dominated, yes. However, I'm from a university that has an even worse reputation as a "posh" uni (Durham) and things are never as bad as the stereotype.
I know that, at undergrad level (not postgrad) it's white and middle class dominated. That can't be denied. However, any "rah" like behaviour will come from the minority (albeit a vocal minority).
Also, Notthingham certainly isn't in the north!