I would recommend staying down-town and not close to the university because the trams stop at around 12pm from Sunday to Wednesday and 1am from Thursday to Saturday. You can take a tram in the morning to go to the university and another one to come back to the town centre after the conference.
Best Western Grand Hôtel Français ***
Right in the town centre, small hotel so book it in advance.
Starting from 120€/night.
Address: 12 Rue du Temple 33000 Bordeaux
Hotel de la presse ***
Right in the town centre, no refund possible even if you shorten you stay, book wisely!
Starting from 75€/night (+10€ for the breakfast).
Address: 6, rue de la Porte-Dijeaux
Quality Hotel Bordeaux Centre ***
Starting from 110€/night (Breakfast included).
Address: 27 Rue Du Parlement St Catherine, 33000, Bordeaux Link
Hotel Gambetta **
Right in the town centre, very small hotel so book it in advance.
Around 68€/night (+7€ for the breakfast)
Address: 66 rue Porte-Dijeaux 33000 Bordeaux
Stars Bordeaux Gare **
Not ideally located to easily reach the university, but still close to the town centre.
Around 56€/night (early booking can get the price down to 35€/night).
Address: 34 rue de Tauzia, 33800 Bordeaux
Not an ideal location, but still close to the town centre. You will have to walk to "Victoire" to catch a tram to the university. The hostel is also closing from 2AM to 5AM, so make sure to be there on time or spend the night partying for a little longer!
Price: 23€/night (Breakfast included)
Address: 22, Cours Barbey 33800 BORDEAUX