I have recently moved to Lancaster, sc and am looking for perennials that do well in the heat down here, with out a lot of watering, I have a berm behind our property I would like to pretty up.

Welcome to the site and welcome to SC!! You can grow zinnias, black Eyed susan, salvia, sage, some herbs, day lilies, butterfly bush, landscape roses, yarrow, amarantha, and more. You will have to water until they are established. Hopefully more SC folks will pop in with more.

Oops. You wanted perennials only...sorry I added some annuals in my reply. Lantana is heat tolerant.

How about some Hens & Chicks? They make a very nice edging and ground cover. I have mine in full sun and they love it there. You can check out all the different varieties in the Sempervivum database.

Assuming it's in tons of sun? Doubtful you'll experience much actual drought in SC, you just want plants that you won't have to water once established, yes? Keeping a layer of mulch on the surface of your planting area will help moisture from evaporating prematurely/unnecessarily.

For baking in the sun, I love Sedums!
http://garden.org/plants/searc...

Many of the Dianthus (sweet Williams) should work well.
http://garden.org/plants/searc...

Purple heart/queen should be hardy for you.
Purple Heart (Tradescantia pallida)

Then there are bulb plants that can be thrown into the mix, Narcissus, Amaryllis, Gladiolus, Lycoris, Agapanthus, Crinum, Hemerocallis.

to ATP and to SC. Living in zone 8, you can grow a wide variety of plants. In addition to the good suggesions already mentioned, here are some others: Gaillardia (blanketflower); Liatris, Asclepias (butterfly weed); Daylilies; Dusty Miller; Baptisia; Heliopsis; Gaura; Agastache; Lavender; Knifophia (Red Hot Poker); Russian Sage; yarrow; sages, verbena and yucca. Have fun choosing your plants, and Happy Gardening!