(Reuters) - ATI Technologies Inc. rode high-profit sales of its graphics chips to on-target third quarter earnings, but warned on Wednesday of lower fourth-quarter results amid a weak market and a shift to new products. Markham, Ontario-based ATI said it expects adjusted earnings of 5 cents to 7 cents a share in the fourth quarter and revenues that are flat or down slightly. On average, nine analysts polled by Thomson/First Call expected adjusted fourth-quarter earnings of 10 cents per share, from a range of estimates between 8 cents and 13 cents. ATI had forecast slight gains in fourth-quarter earnings and revenues. It met third-quarter estimates with adjusted earnings of 8 cents a share.