look at job prospects after graduation

after all it's why you go to a uni.

some lower ranked unis have better job prospects because they help you more or are sponsored by companies that look directly at graduate scores and offer the ones they want jobs.

My uni is quite middle ground, but the computer science department is in good standing :3

A good idea is also to check the dpertment rankings, for example Oxford and Cambridge in the UK may be famous (and the highest ranked overall) but in a couple of subjects it is outclassed by other universities such as Southampton or Warwick.

Sometimes sadly, headhunters find that if the uni is more prestigious, it looks good to have them on the team as it were.