Hardware accelerator architectures for clustering are described. A hardware accelerator includes sparse tiles and very/hyper sparse tiles. The sparse tile(s) execute operations for a clustering task involving a matrix. Each sparse tile includes a first plurality of processing units to operate upon a first plurality of blocks of the matrix that have been streamed to one or more random access memories of the sparse tiles over a high bandwidth interface from a first memory unit. Each of the very/hyper sparse tiles are to execute operations for the clustering task involving the matrix. Each of the very/hyper sparse tiles includes a second plurality of processing units to operate upon a second plurality of blocks of the matrix that have been randomly accessed over a low-latency interface from a second memory unit.