Ta'er Monastery from Xining Railway Station

Could anyone advise me on getting to Ta'er monastery from the railway station in a timely manner? I've read that the bus leaving the railway station takes 1 hr and 40 min to get to the monastery. Also I know there's a bus from the City Road Bus Station that takes only 45 min? How often do they run and how much would a taxi cost from the railway station to the bus station? Is it easy to take the same bus back? Thanks in advance!