The invention provides extended line width memory-side cache systems and methods. The present disclosure provides techniques for implementing an apparatus, which includes processing circuitry that performs an operation based a target data block, a processor-side cache that implements a first cache line, a memory-side cache that implements a second cache line having line width greater than the first cache line, and a memory array. The apparatus includes one or more memory controllers that, when the target data block results in a cache miss, determine a row address that identifies a memory cellrow as storing the target data block, instruct the memory array to successively output multiple data blocks from the memory cell row to enable the memory-side cache to store each of the multiple of data blocks in the second cache line, and instruct the memory-side cache to output the target data block to a coherency bus to enable the processing circuitry to perform the operation based on the target data block.