Abstract: In this paper we present an approach to efficiently trace single rays on the Cell Processor, instead of using ray packets. To benefit from the performance of this processor, a data structure is chosen which allows traversal without excessive accesses to main memory. Together with careful optimization for SIMD processing, a performance comparable to a packet based ray tracer, running on the same hardware, is achieved. In special cases, when the coherency of the traced rays get very low, it even outperforms the packet based approach.