I use a basic low-end corded B&D drill. I think is 500W.

I only have the silver colour bits and use it both on concrete and tiles. My technique is use the smallest bit (2mm-3mm) first to drill a hole slowly into 2-4cm depth. Then only use the 5-8mm bit to widen it. So far never break a single tile. I drill both between tiles and directly on tiles. This make need some practise, try on some spare/broken tiles first.

Remember to disable the hammer-drill function, this is for concrete only.