The new Haswell SoC is possibly going to contain a rather impressive 128MB of eDRAM on board. Way back in the mists of 2012, Intel had plans to add eDRAM into the Ivy Bridge platform, but was canned. The problem with adding eDRAM is too fold – heat and cost.
The e in the GT3e actually stands for embedded ram, while the GT3 signifies the GPU configuration that the SoC will be using. In this case, 40EUs. The purpose of these chips will be for integrated devices, hence the GBA package (soldered directly onto the board). A list of papers was shown off at the 2013 VLSI Technology at Symposium in Kyoto. This papers title is believed to offer the clue to the contents of the SoC.
“A 22nm High Performance Embedded DRAM SoC Technology Featuring Tri-Gate Transistors and MIMCAP COB”
David Kanter, from RealWorldTech (and this has been somewhat validated from other sources) that the new Haswell GT3E will come with 128MB of eDRAM connected to the main SoC via a 512-bit bus. Using eDRAM vs. commodity DDR3 makes sense as the former is easier to integrate into Intel’s current fabs. According to leaked documents the embedded eDRAM will act as a cache (Level 4), which will vastly improve the GPU and CPU performance, particularly for server based environments and for us ‘normal’ customers, it’ll be a lot better for games. Bare in mind, that it is only 128MB, which is a far cry away from the large amounts of VRAM on a traditional dedicated card. But, it is a significant step forward for integrated graphics, especially with Intel, who’ve been worse than AMD’s SoCs.
Bare in mind, that the Playstation 4 (and likely, next generation XBox) are using the AMD Jaguar, which combined with the GPU and CPU, also have an integrated GDDR5 controller on the SoC. The purpose here (as I’ve mentioned so many times in videos and other articles) is to cure one of the biggest banes of integrated / SoC graphics – memory bandwidth.