A data access system including a processor, multiple cache modules for the main memory, and a storage drive. The cache modules include a FLC controller and a main memory cache. The multiple cache modules function as main memory. The processor sends read/write requests (with physical address) to the cache module. The cache module includes two or more stages with each stage including a FLC controller and DRAM (with associated controller). If the first stage FLC module does not include the physical address, the request is forwarded to a second stage FLC module. If the second stage FLC module does not include the physical address, the request is forwarded to the storage drive, a partition reserved for main memory. The first stage FLC module has high speed, lower power operation while the second stage FLC is a low-cost implementation. Multiple FLC modules may connect to the processor in parallel.