The Iris Pro 5200 has 128MB DRAM ("Crystalwell") embedded in the CPU/GPU package. This one is in the 15 inch model. The Non-"Pro" Iris 5100 in the 13 inch Macbo

The Iris Pro 5200 has 128MB DRAM ("Crystalwell") embedded in the CPU/GPU package. This one is in the 15 inch model. The Non-"Pro" Iris 5100 in the 13 inch Macbook is the same GPU, same clock speed, but without the embedded DRAM. Depending on the task, the 5200 seems to be up to twice as fast. Also, the DRAM is actually a huge Level 4 cache for the CPU, which means that it should speed up other things than graphics as well. Benchmarks: * http://www.notebookcheck.net/Intel-Iris-Graphics-5100.91977.0.html http://www.notebookcheck.net/Intel-Iris-Graphics-5100.91977.... * http://www.notebookcheck.net/Intel-Iris-Pro-Graphics-5200.90965.0.html http://www.notebookcheck.net/Intel-Iris-Pro-Graphics-5200.90...