This paper studies the radio capacity improvement provided by an HSPA+ key feature, dual-cell, combined with MIMO. The proposed method combines drive test measurements, link-level simulations, and a queuing theory-based statistical capacity model, thereby providing a reliable estimate of the network radio capacity. Simulation results show that dual cell combined with MIMO and non-linear receivers using Successive Interference Cancellation (SIC) significantly increases network radio capacity. These results confirm that HSPA networks evolutions are promising.