Abstract: Recent accomplishments in the computer simulation of black oil reservoirs have created a demand for the visualization of very large models. In this paper, we present a distributed system for the rendering of such models. Following recent trends in the high performance computing area, the system is intended to make the visualization of these models available to lightweight clients on corporate networks, through the use of a cluster of inexpensive off-the-shelf PCs equipped with multiple GPUs. The proposed system uses a sort-last approach and supports a diverse set of visualization techniques. Through an efficient use of each GPU and a partial composition stage on each cluster node, our solution tackles the scalability issues that arise when using mid-to-large GPU clusters. Experimental results show that our implementation can sustain the visualization of models with up to 60 million cells at interactive rates, using a cluster with 16 nodes, each one equipped with 4 GPUs. Experimental results also demonstrate the scalability of the proposed solution.